[RFC PATCH 5/7] DMA: tegra-apb: Move common code into separate source files
From: Jon Hunter
Date: Tue Aug 18 2015 - 09:50:37 EST
Move code that is common between the Tegra20-APB DMA and Tegra210 ADMA
driver into separate source files.
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
drivers/dma/Kconfig | 4 +
drivers/dma/Makefile | 1 +
drivers/dma/tegra-common.c | 733 ++++++++++++++++++++++++++++++++++
drivers/dma/tegra-common.h | 226 +++++++++++
drivers/dma/tegra20-apb-dma.c | 910 +-----------------------------------------
5 files changed, 972 insertions(+), 902 deletions(-)
create mode 100644 drivers/dma/tegra-common.c
create mode 100644 drivers/dma/tegra-common.h
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index ff50af3f1bb0..dd79b0bf0876 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -189,10 +189,14 @@ config TXX9_DMAC
Support the TXx9 SoC internal DMA controller. This can be
integrated in chips such as the Toshiba TX4927/38/39.
+config TEGRA_DMA_COMMON
+ bool
+
config TEGRA20_APB_DMA
bool "NVIDIA Tegra20 APB DMA support"
depends on ARCH_TEGRA
select DMA_ENGINE
+ select TEGRA_DMA_COMMON
help
Support for the NVIDIA Tegra20 APB DMA controller driver. The
DMA controller is having multiple DMA channel which can be
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 264eb3c52446..d9c2bf5ef0bd 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_SIRF_DMA) += sirf-dma.o
obj-$(CONFIG_TI_EDMA) += edma.o
obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o
+obj-$(CONFIG_TEGRA_DMA_COMMON) += tegra-common.o
obj-$(CONFIG_S3C24XX_DMAC) += s3c24xx-dma.o
obj-$(CONFIG_PL330_DMA) += pl330.o
obj-$(CONFIG_PCH_DMA) += pch_dma.o
diff --git a/drivers/dma/tegra-common.c b/drivers/dma/tegra-common.c
new file mode 100644
index 000000000000..fff0a143f5bb
--- /dev/null
+++ b/drivers/dma/tegra-common.c
@@ -0,0 +1,733 @@
+/*
+ * Helper functions for NVIDIA DMA drivers.
+ *
+ * Copyright (c) 2015, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#include "dmaengine.h"
+#include "tegra-common.h"
+
+static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
+{
+ struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
+ unsigned long flags;
+ dma_cookie_t cookie;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ dma_desc->dma_status = DMA_IN_PROGRESS;
+ cookie = dma_cookie_assign(&dma_desc->txd);
+ list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return cookie;
+}
+
+/* Get DMA desc from free list, if not there then allocate it. */
+static struct tegra_dma_desc *tegra_dma_desc_get(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_desc *dma_desc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+
+ /* Do not allocate if desc are waiting for ack */
+ list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
+ if (async_tx_test_ack(&dma_desc->txd)) {
+ list_del(&dma_desc->node);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ dma_desc->txd.flags = 0;
+ return dma_desc;
+ }
+ }
+
+ spin_unlock_irqrestore(&tdc->lock, flags);
+
+ /* Allocate DMA desc */
+ dma_desc = kzalloc(sizeof(*dma_desc), GFP_ATOMIC);
+ if (!dma_desc)
+ return NULL;
+
+ dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
+ dma_desc->txd.tx_submit = tegra_dma_tx_submit;
+ dma_desc->txd.flags = 0;
+ return dma_desc;
+}
+
+static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
+ struct tegra_dma_desc *dma_desc)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ if (!list_empty(&dma_desc->tx_list))
+ list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
+ list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+}
+
+static struct tegra_dma_sg_req *tegra_dma_sg_req_get(
+ struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *sg_req = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ if (!list_empty(&tdc->free_sg_req)) {
+ sg_req = list_first_entry(&tdc->free_sg_req,
+ typeof(*sg_req), node);
+ list_del(&sg_req->node);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return sg_req;
+ }
+ spin_unlock_irqrestore(&tdc->lock, flags);
+
+ return kzalloc(sizeof(struct tegra_dma_sg_req), GFP_ATOMIC);
+}
+
+static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *nsg_req)
+{
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ unsigned long status;
+
+ /*
+ * The DMA controller reloads the new configuration for next transfer
+ * after last burst of current transfer completes.
+ * If there is no IEC status then this makes sure that last burst
+ * has not be completed. There may be case that last burst is on
+ * flight and so it can complete but because DMA is paused, it
+ * will not generates interrupt as well as not reload the new
+ * configuration.
+ * If there is already IEC status then interrupt handler need to
+ * load new configuration.
+ */
+ ops->pause(tdc, false);
+ status = ops->irq_status(tdc);
+
+ /*
+ * If interrupt is pending then do nothing as the ISR will handle
+ * the programing for new request.
+ */
+ if (status) {
+ dev_err(tdc2dev(tdc),
+ "Skipping new configuration as interrupt is pending\n");
+ ops->resume(tdc);
+ return;
+ }
+
+ /* Safe to program new configuration */
+ ops->program(tdc, nsg_req);
+ ops->resume(tdc);
+}
+
+static void tdc_start_head_req(struct tegra_dma_channel *tdc)
+{
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ struct tegra_dma_sg_req *sg_req;
+
+ if (list_empty(&tdc->pending_sg_req))
+ return;
+
+ sg_req = list_first_entry(&tdc->pending_sg_req,
+ typeof(*sg_req), node);
+ ops->start(tdc, sg_req);
+ sg_req->configured = true;
+ tdc->busy = true;
+}
+
+static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *hsgreq;
+ struct tegra_dma_sg_req *hnsgreq;
+
+ if (list_empty(&tdc->pending_sg_req))
+ return;
+
+ hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
+ if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
+ hnsgreq = list_first_entry(&hsgreq->node,
+ typeof(*hnsgreq), node);
+ tegra_dma_configure_for_next(tdc, hnsgreq);
+ }
+}
+
+static inline int get_current_xferred_count(struct tegra_dma_sg_req *sg_req,
+ unsigned long wcount)
+{
+ return sg_req->req_len - wcount;
+}
+
+static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+
+ while (!list_empty(&tdc->pending_sg_req)) {
+ sgreq = list_first_entry(&tdc->pending_sg_req,
+ typeof(*sgreq), node);
+ list_move_tail(&sgreq->node, &tdc->free_sg_req);
+ if (sgreq->last_sg) {
+ dma_desc = sgreq->dma_desc;
+ dma_desc->dma_status = DMA_ERROR;
+ list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
+
+ /* Add in cb list if it is not there. */
+ if (!dma_desc->cb_count)
+ list_add_tail(&dma_desc->cb_node,
+ &tdc->cb_desc);
+ dma_desc->cb_count++;
+ }
+ }
+ tdc->isr_handler = NULL;
+}
+
+static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *last_sg_req,
+ bool to_terminate)
+{
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ struct tegra_dma_sg_req *hsgreq = NULL;
+
+ if (list_empty(&tdc->pending_sg_req)) {
+ dev_err(tdc2dev(tdc), "Dma is running without req\n");
+ ops->stop(tdc);
+ return false;
+ }
+
+ /*
+ * Check that head req on list should be in flight.
+ * If it is not in flight then abort transfer as
+ * looping of transfer can not continue.
+ */
+ hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
+ if (!hsgreq->configured) {
+ ops->stop(tdc);
+ dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
+ tegra_dma_abort_all(tdc);
+ return false;
+ }
+
+ /* Configure next request */
+ if (!to_terminate)
+ tdc_configure_next_head_desc(tdc);
+ return true;
+}
+
+static void handle_once_dma_done(struct tegra_dma_channel *tdc,
+ bool to_terminate)
+{
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+
+ tdc->busy = false;
+ sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
+ dma_desc = sgreq->dma_desc;
+ dma_desc->bytes_transferred += sgreq->req_len;
+
+ list_del(&sgreq->node);
+ if (sgreq->last_sg) {
+ dma_desc->dma_status = DMA_COMPLETE;
+ dma_cookie_complete(&dma_desc->txd);
+ if (!dma_desc->cb_count)
+ list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
+ dma_desc->cb_count++;
+ list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
+ }
+ list_add_tail(&sgreq->node, &tdc->free_sg_req);
+
+ /* Do not start DMA if it is going to be terminate */
+ if (to_terminate || list_empty(&tdc->pending_sg_req))
+ return;
+
+ tdc_start_head_req(tdc);
+}
+
+static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
+ bool to_terminate)
+{
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+ bool st;
+
+ sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
+ dma_desc = sgreq->dma_desc;
+ dma_desc->bytes_transferred += sgreq->req_len;
+
+ /* Callback need to be call */
+ if (!dma_desc->cb_count)
+ list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
+ dma_desc->cb_count++;
+
+ /* If not last req then put at end of pending list */
+ if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
+ list_move_tail(&sgreq->node, &tdc->pending_sg_req);
+ sgreq->configured = false;
+ st = handle_continuous_head_request(tdc, sgreq, to_terminate);
+ if (!st)
+ dma_desc->dma_status = DMA_ERROR;
+ }
+}
+
+int tegra_dma_slave_config(struct dma_chan *dc,
+ struct dma_slave_config *sconfig)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+
+ if (!list_empty(&tdc->pending_sg_req)) {
+ dev_err(tdc2dev(tdc), "Configuration not allowed\n");
+ return -EBUSY;
+ }
+
+ memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
+ if (!tdc->slave_id)
+ tdc->slave_id = sconfig->slave_id;
+ tdc->config_init = true;
+ return 0;
+}
+
+void tegra_dma_tasklet(unsigned long data)
+{
+ struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
+ dma_async_tx_callback callback = NULL;
+ void *callback_param = NULL;
+ struct tegra_dma_desc *dma_desc;
+ unsigned long flags;
+ int cb_count;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ while (!list_empty(&tdc->cb_desc)) {
+ dma_desc = list_first_entry(&tdc->cb_desc,
+ typeof(*dma_desc), cb_node);
+ list_del(&dma_desc->cb_node);
+ callback = dma_desc->txd.callback;
+ callback_param = dma_desc->txd.callback_param;
+ cb_count = dma_desc->cb_count;
+ dma_desc->cb_count = 0;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ while (cb_count-- && callback)
+ callback(callback_param);
+ spin_lock_irqsave(&tdc->lock, flags);
+ }
+ spin_unlock_irqrestore(&tdc->lock, flags);
+}
+
+irqreturn_t tegra_dma_isr(int irq, void *dev_id)
+{
+ struct tegra_dma_channel *tdc = dev_id;
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ unsigned long status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+
+ status = ops->irq_clear(tdc);
+ if (status) {
+ tdc->isr_handler(tdc, false);
+ tasklet_schedule(&tdc->tasklet);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ dev_info(tdc2dev(tdc),
+ "Interrupt already served status 0x%08lx\n", status);
+ return IRQ_NONE;
+}
+
+void tegra_dma_issue_pending(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ if (list_empty(&tdc->pending_sg_req)) {
+ dev_err(tdc2dev(tdc), "No DMA request\n");
+ goto end;
+ }
+ if (!tdc->busy) {
+ tdc_start_head_req(tdc);
+
+ /* Continuous single mode: Configure next req */
+ if (tdc->cyclic) {
+ /*
+ * Wait for 1 burst time for configure DMA for
+ * next transfer.
+ */
+ udelay(tdc->tdma->chip_data->burst_time);
+ tdc_configure_next_head_desc(tdc);
+ }
+ }
+end:
+ spin_unlock_irqrestore(&tdc->lock, flags);
+}
+
+int tegra_dma_terminate_all(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+ unsigned long flags;
+ unsigned long status;
+ unsigned long wcount;
+ bool was_busy;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ if (list_empty(&tdc->pending_sg_req)) {
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return 0;
+ }
+
+ if (!tdc->busy)
+ goto skip_dma_stop;
+
+ /* Pause DMA before checking the queue status */
+ ops->pause(tdc, true);
+
+ status = ops->irq_status(tdc);
+ if (status) {
+ dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
+ tdc->isr_handler(tdc, true);
+ }
+
+ wcount = ops->get_xfer_count(tdc);
+
+ was_busy = tdc->busy;
+ ops->stop(tdc);
+
+ if (!list_empty(&tdc->pending_sg_req) && was_busy) {
+ sgreq = list_first_entry(&tdc->pending_sg_req,
+ typeof(*sgreq), node);
+ sgreq->dma_desc->bytes_transferred +=
+ get_current_xferred_count(sgreq, wcount);
+ }
+ ops->resume(tdc);
+
+skip_dma_stop:
+ tegra_dma_abort_all(tdc);
+
+ while (!list_empty(&tdc->cb_desc)) {
+ dma_desc = list_first_entry(&tdc->cb_desc,
+ typeof(*dma_desc), cb_node);
+ list_del(&dma_desc->cb_node);
+ dma_desc->cb_count = 0;
+ }
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return 0;
+}
+
+enum dma_status tegra_dma_tx_status(struct dma_chan *dc, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma_desc *dma_desc;
+ struct tegra_dma_sg_req *sg_req;
+ enum dma_status ret;
+ unsigned long flags;
+ unsigned int residual;
+
+ ret = dma_cookie_status(dc, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+
+ /* Check on wait_ack desc status */
+ list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
+ if (dma_desc->txd.cookie == cookie) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ ret = dma_desc->dma_status;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+ }
+
+ /* Check in pending list */
+ list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
+ dma_desc = sg_req->dma_desc;
+ if (dma_desc->txd.cookie == cookie) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ ret = dma_desc->dma_status;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+ }
+
+ dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+}
+
+struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
+ struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
+ enum dma_transfer_direction direction, unsigned long flags,
+ void *context)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ struct tegra_dma_desc *dma_desc;
+ unsigned int i;
+ struct scatterlist *sg;
+ struct list_head req_list;
+ struct tegra_dma_sg_req sg_base, *sg_req = NULL;
+
+ if (!tdc->config_init) {
+ dev_err(tdc2dev(tdc), "dma channel is not configured\n");
+ return NULL;
+ }
+ if (sg_len < 1) {
+ dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
+ return NULL;
+ }
+
+ if (ops->get_xfer_params_sg(tdc, &sg_base, direction, flags) < 0)
+ return NULL;
+
+ INIT_LIST_HEAD(&req_list);
+
+ dma_desc = tegra_dma_desc_get(tdc);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
+ return NULL;
+ }
+ INIT_LIST_HEAD(&dma_desc->tx_list);
+ INIT_LIST_HEAD(&dma_desc->cb_node);
+ dma_desc->cb_count = 0;
+ dma_desc->bytes_requested = 0;
+ dma_desc->bytes_transferred = 0;
+ dma_desc->dma_status = DMA_IN_PROGRESS;
+
+ /* Make transfer requests */
+ for_each_sg(sgl, sg, sg_len, i) {
+ u32 len, mem;
+
+ mem = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+ if ((len & 3) || (mem & 3) ||
+ (len > tdc->tdma->chip_data->max_dma_count)) {
+ dev_err(tdc2dev(tdc),
+ "Dma length/memory address is not supported\n");
+ tegra_dma_desc_put(tdc, dma_desc);
+ return NULL;
+ }
+
+ sg_req = tegra_dma_sg_req_get(tdc);
+ if (!sg_req) {
+ dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
+ tegra_dma_desc_put(tdc, dma_desc);
+ return NULL;
+ }
+
+ dma_desc->bytes_requested += len;
+
+ ops->set_xfer_params(tdc, sg_req, &sg_base, direction, mem,
+ len);
+ sg_req->dma_desc = dma_desc;
+
+ list_add_tail(&sg_req->node, &dma_desc->tx_list);
+ }
+ sg_req->last_sg = true;
+ if (flags & DMA_CTRL_ACK)
+ dma_desc->txd.flags = DMA_CTRL_ACK;
+
+ /*
+ * Make sure that mode should not be conflicting with currently
+ * configured mode.
+ */
+ if (!tdc->isr_handler) {
+ tdc->isr_handler = handle_once_dma_done;
+ tdc->cyclic = false;
+ } else {
+ if (tdc->cyclic) {
+ dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
+ tegra_dma_desc_put(tdc, dma_desc);
+ return NULL;
+ }
+ }
+
+ return &dma_desc->txd;
+}
+
+struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
+ struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
+ size_t period_len, enum dma_transfer_direction direction,
+ unsigned long flags)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ const struct tegra_dma_ops *ops = tdc->tdma->ops;
+ struct tegra_dma_desc *dma_desc = NULL;
+ struct tegra_dma_sg_req sg_base, *sg_req = NULL;
+ int len;
+ size_t remain_len;
+ dma_addr_t mem = buf_addr;
+
+ if (!buf_len || !period_len) {
+ dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
+ return NULL;
+ }
+
+ if (!tdc->config_init) {
+ dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
+ return NULL;
+ }
+
+ /*
+ * We allow to take more number of requests till DMA is
+ * not started. The driver will loop over all requests.
+ * Once DMA is started then new requests can be queued only after
+ * terminating the DMA.
+ */
+ if (tdc->busy) {
+ dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
+ return NULL;
+ }
+
+ /*
+ * We only support cycle transfer when buf_len is multiple of
+ * period_len.
+ */
+ if (buf_len % period_len) {
+ dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
+ return NULL;
+ }
+
+ len = period_len;
+ if ((len & 3) || (buf_addr & 3) ||
+ (len > tdc->tdma->chip_data->max_dma_count)) {
+ dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
+ return NULL;
+ }
+
+ if (ops->get_xfer_params_cyclic(tdc, &sg_base, direction, flags) < 0)
+ return NULL;
+
+ dma_desc = tegra_dma_desc_get(tdc);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "not enough descriptors available\n");
+ return NULL;
+ }
+
+ INIT_LIST_HEAD(&dma_desc->tx_list);
+ INIT_LIST_HEAD(&dma_desc->cb_node);
+ dma_desc->cb_count = 0;
+
+ dma_desc->bytes_transferred = 0;
+ dma_desc->bytes_requested = buf_len;
+ remain_len = buf_len;
+
+ /* Split transfer equal to period size */
+ while (remain_len) {
+ sg_req = tegra_dma_sg_req_get(tdc);
+ if (!sg_req) {
+ dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
+ tegra_dma_desc_put(tdc, dma_desc);
+ return NULL;
+ }
+
+ ops->set_xfer_params(tdc, sg_req, &sg_base, direction, mem,
+ len);
+ sg_req->dma_desc = dma_desc;
+
+ list_add_tail(&sg_req->node, &dma_desc->tx_list);
+ remain_len -= len;
+ mem += len;
+ }
+ sg_req->last_sg = true;
+ if (flags & DMA_CTRL_ACK)
+ dma_desc->txd.flags = DMA_CTRL_ACK;
+
+ /*
+ * Make sure that mode should not be conflicting with currently
+ * configured mode.
+ */
+ if (!tdc->isr_handler) {
+ tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
+ tdc->cyclic = true;
+ } else {
+ if (!tdc->cyclic) {
+ dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
+ tegra_dma_desc_put(tdc, dma_desc);
+ return NULL;
+ }
+ }
+
+ return &dma_desc->txd;
+}
+
+int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma *tdma = tdc->tdma;
+
+ dma_cookie_init(&tdc->dma_chan);
+ tdc->config_init = false;
+
+ return pm_runtime_get_sync(tdma->dev);
+}
+
+void tegra_dma_free_chan_resources(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma *tdma = tdc->tdma;
+
+ struct tegra_dma_desc *dma_desc;
+ struct tegra_dma_sg_req *sg_req;
+ struct list_head dma_desc_list;
+ struct list_head sg_req_list;
+ unsigned long flags;
+
+ INIT_LIST_HEAD(&dma_desc_list);
+ INIT_LIST_HEAD(&sg_req_list);
+
+ dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
+
+ if (tdc->busy)
+ tegra_dma_terminate_all(dc);
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ list_splice_init(&tdc->pending_sg_req, &sg_req_list);
+ list_splice_init(&tdc->free_sg_req, &sg_req_list);
+ list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
+ INIT_LIST_HEAD(&tdc->cb_desc);
+ tdc->config_init = false;
+ tdc->isr_handler = NULL;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+
+ while (!list_empty(&dma_desc_list)) {
+ dma_desc = list_first_entry(&dma_desc_list,
+ typeof(*dma_desc), node);
+ list_del(&dma_desc->node);
+ kfree(dma_desc);
+ }
+
+ while (!list_empty(&sg_req_list)) {
+ sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
+ list_del(&sg_req->node);
+ kfree(sg_req);
+ }
+ pm_runtime_put(tdma->dev);
+
+ tdc->slave_id = 0;
+}
diff --git a/drivers/dma/tegra-common.h b/drivers/dma/tegra-common.h
new file mode 100644
index 000000000000..e0d4d2b13cb8
--- /dev/null
+++ b/drivers/dma/tegra-common.h
@@ -0,0 +1,226 @@
+/*
+ * Copyright (c) 2015, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * tegra_dma_chip_data Tegra chip specific DMA data
+ * @nr_channels: Number of channels available in the controller.
+ * @channel_reg_size: Channel register size/stride.
+ * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
+ * @support_channel_pause: Support channel wise pause of dma.
+ * @support_separate_wcount_reg: Support separate word count register.
+ */
+struct tegra_dma_chip_data {
+ int burst_time;
+ int nr_channels;
+ int channel_reg_size;
+ int max_dma_count;
+ bool support_channel_pause;
+ bool support_separate_wcount_reg;
+};
+
+/*
+ * DMA channel registers
+ */
+struct tegra_dma_channel_regs {
+ unsigned long csr;
+ unsigned long ahb_ptr;
+ unsigned long apb_ptr;
+ unsigned long ahb_seq;
+ unsigned long apb_seq;
+ unsigned long wcount;
+};
+
+/*
+ * tegra_dma_sg_req: Dma request details to configure hardware. This
+ * contains the details for one transfer to configure DMA hw.
+ * The client's request for data transfer can be broken into multiple
+ * sub-transfer as per requester details and hw support.
+ * This sub transfer get added in the list of transfer and point to Tegra
+ * DMA descriptor which manages the transfer details.
+ */
+struct tegra_dma_sg_req {
+ struct tegra_dma_channel_regs ch_regs;
+ int req_len;
+ bool configured;
+ bool last_sg;
+ struct list_head node;
+ struct tegra_dma_desc *dma_desc;
+};
+
+/*
+ * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
+ * This descriptor keep track of transfer status, callbacks and request
+ * counts etc.
+ */
+struct tegra_dma_desc {
+ struct dma_async_tx_descriptor txd;
+ int bytes_requested;
+ int bytes_transferred;
+ enum dma_status dma_status;
+ struct list_head node;
+ struct list_head tx_list;
+ struct list_head cb_node;
+ int cb_count;
+};
+
+struct tegra_dma_channel;
+
+typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
+ bool to_terminate);
+
+/*
+ * tegra_dma_channel: Channel specific information
+ */
+struct tegra_dma_channel {
+ struct dma_chan dma_chan;
+ char name[30];
+ bool config_init;
+ int id;
+ int irq;
+ void __iomem *chan_addr;
+ spinlock_t lock;
+ bool busy;
+ struct tegra_dma *tdma;
+ bool cyclic;
+
+ /* Different lists for managing the requests */
+ struct list_head free_sg_req;
+ struct list_head pending_sg_req;
+ struct list_head free_dma_desc;
+ struct list_head cb_desc;
+
+ /* ISR handler and tasklet for bottom half of isr handling */
+ dma_isr_handler isr_handler;
+ struct tasklet_struct tasklet;
+
+ /* Channel-slave specific configuration */
+ unsigned int slave_id;
+ struct dma_slave_config dma_sconfig;
+ struct tegra_dma_channel_regs channel_reg;
+};
+
+/*
+ * tegra_dma_ops: Tegra DMA function table
+ */
+struct tegra_dma_ops {
+ u32 (*get_xfer_count)(struct tegra_dma_channel *tdc);
+ int (*get_xfer_params_cyclic)(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *sg_req,
+ enum dma_transfer_direction direction,
+ unsigned int flags);
+ int (*get_xfer_params_sg)(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *sg_req,
+ enum dma_transfer_direction direction,
+ unsigned int flags);
+ u32 (*irq_clear)(struct tegra_dma_channel *tdc);
+ u32 (*irq_status)(struct tegra_dma_channel *tdc);
+ void (*pause)(struct tegra_dma_channel *tdc,
+ bool wait_for_burst_complete);
+ void (*program)(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *sg_req);
+ void (*resume)(struct tegra_dma_channel *tdc);
+ void (*set_xfer_params)(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *sg_req,
+ struct tegra_dma_sg_req *sg_base,
+ enum dma_transfer_direction direction,
+ u32 mem, u32 len);
+ void (*start)(struct tegra_dma_channel *tdc,
+ struct tegra_dma_sg_req *sg_req);
+ void (*stop)(struct tegra_dma_channel *tdc);
+};
+
+/*
+ * tegra_dma: Tegra DMA specific information
+ */
+struct tegra_dma {
+ struct dma_device dma_dev;
+ struct device *dev;
+ struct clk *dma_clk;
+ struct reset_control *rst;
+ spinlock_t global_lock;
+ void __iomem *base_addr;
+ const struct tegra_dma_chip_data *chip_data;
+ const struct tegra_dma_ops *ops;
+
+ /*
+ * Counter for managing global pausing of the DMA controller.
+ * Only applicable for devices that don't support individual
+ * channel pausing.
+ */
+ u32 global_pause_count;
+
+ /* Some register need to be cache before suspend */
+ u32 reg_gen;
+
+ /* Last member of the structure */
+ struct tegra_dma_channel channels[0];
+};
+
+static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
+{
+ writel(val, tdma->base_addr + reg);
+}
+
+static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
+{
+ return readl(tdma->base_addr + reg);
+}
+
+static inline void tdc_write(struct tegra_dma_channel *tdc,
+ u32 reg, u32 val)
+{
+ writel(val, tdc->chan_addr + reg);
+}
+
+static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
+{
+ return readl(tdc->chan_addr + reg);
+}
+
+static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
+{
+ return container_of(dc, struct tegra_dma_channel, dma_chan);
+}
+
+static inline struct tegra_dma_desc *txd_to_tegra_dma_desc(
+ struct dma_async_tx_descriptor *td)
+{
+ return container_of(td, struct tegra_dma_desc, txd);
+}
+
+static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
+{
+ return &tdc->dma_chan.dev->device;
+}
+
+irqreturn_t tegra_dma_isr(int irq, void *dev_id);
+void tegra_dma_issue_pending(struct dma_chan *dc);
+int tegra_dma_slave_config(struct dma_chan *dc,
+ struct dma_slave_config *sconfig);
+void tegra_dma_tasklet(unsigned long data);
+enum dma_status tegra_dma_tx_status(struct dma_chan *dc, dma_cookie_t cookie,
+ struct dma_tx_state *txstate);
+int tegra_dma_terminate_all(struct dma_chan *dc);
+struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
+ struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
+ enum dma_transfer_direction direction, unsigned long flags,
+ void *context);
+struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
+ struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
+ size_t period_len, enum dma_transfer_direction direction,
+ unsigned long flags);
+int tegra_dma_alloc_chan_resources(struct dma_chan *dc);
+void tegra_dma_free_chan_resources(struct dma_chan *dc);
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 7947acdf23db..0895732aaa28 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -38,6 +38,8 @@
#include "dmaengine.h"
+#include "tegra-common.h"
+
#define TEGRA_APBDMA_GENERAL 0x0
#define TEGRA_APBDMA_GENERAL_ENABLE BIT(31)
@@ -114,279 +116,9 @@
/* Channel base address offset from APBDMA base address */
#define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000
-struct tegra_dma;
-
-/*
- * tegra_dma_chip_data Tegra chip specific DMA data
- * @nr_channels: Number of channels available in the controller.
- * @channel_reg_size: Channel register size/stride.
- * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
- * @support_channel_pause: Support channel wise pause of dma.
- * @support_separate_wcount_reg: Support separate word count register.
- */
-struct tegra_dma_chip_data {
- int nr_channels;
- int channel_reg_size;
- int max_dma_count;
- bool support_channel_pause;
- bool support_separate_wcount_reg;
-};
-
-/* DMA channel registers */
-struct tegra_dma_channel_regs {
- unsigned long csr;
- unsigned long ahb_ptr;
- unsigned long apb_ptr;
- unsigned long ahb_seq;
- unsigned long apb_seq;
- unsigned long wcount;
-};
-
-/*
- * tegra_dma_sg_req: Dma request details to configure hardware. This
- * contains the details for one transfer to configure DMA hw.
- * The client's request for data transfer can be broken into multiple
- * sub-transfer as per requester details and hw support.
- * This sub transfer get added in the list of transfer and point to Tegra
- * DMA descriptor which manages the transfer details.
- */
-struct tegra_dma_sg_req {
- struct tegra_dma_channel_regs ch_regs;
- int req_len;
- bool configured;
- bool last_sg;
- struct list_head node;
- struct tegra_dma_desc *dma_desc;
-};
-
-/*
- * tegra_dma_desc: Tegra DMA descriptors which manages the client requests.
- * This descriptor keep track of transfer status, callbacks and request
- * counts etc.
- */
-struct tegra_dma_desc {
- struct dma_async_tx_descriptor txd;
- int bytes_requested;
- int bytes_transferred;
- enum dma_status dma_status;
- struct list_head node;
- struct list_head tx_list;
- struct list_head cb_node;
- int cb_count;
-};
-
-struct tegra_dma_channel;
-
-typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc,
- bool to_terminate);
-
-/* tegra_dma_channel: Channel specific information */
-struct tegra_dma_channel {
- struct dma_chan dma_chan;
- char name[30];
- bool config_init;
- int id;
- int irq;
- void __iomem *chan_addr;
- spinlock_t lock;
- bool busy;
- struct tegra_dma *tdma;
- bool cyclic;
-
- /* Different lists for managing the requests */
- struct list_head free_sg_req;
- struct list_head pending_sg_req;
- struct list_head free_dma_desc;
- struct list_head cb_desc;
-
- /* ISR handler and tasklet for bottom half of isr handling */
- dma_isr_handler isr_handler;
- struct tasklet_struct tasklet;
-
- /* Channel-slave specific configuration */
- unsigned int slave_id;
- struct dma_slave_config dma_sconfig;
- struct tegra_dma_channel_regs channel_reg;
-};
-
-struct tegra_dma_ops {
- u32 (*get_xfer_count)(struct tegra_dma_channel *tdc);
- int (*get_xfer_params_cyclic)(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *sg_req,
- enum dma_transfer_direction direction,
- unsigned int flags);
- int (*get_xfer_params_sg)(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *sg_req,
- enum dma_transfer_direction direction,
- unsigned int flags);
- u32 (*irq_clear)(struct tegra_dma_channel *tdc);
- u32 (*irq_status)(struct tegra_dma_channel *tdc);
- void (*pause)(struct tegra_dma_channel *tdc,
- bool wait_for_burst_complete);
- void (*program)(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *sg_req);
- void (*resume)(struct tegra_dma_channel *tdc);
- void (*set_xfer_params)(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *sg_req,
- struct tegra_dma_sg_req *sg_base,
- enum dma_transfer_direction direction,
- u32 mem, u32 len);
- void (*start)(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *sg_req);
- void (*stop)(struct tegra_dma_channel *tdc);
-};
-
-/* tegra_dma: Tegra DMA specific information */
-struct tegra_dma {
- struct dma_device dma_dev;
- struct device *dev;
- struct clk *dma_clk;
- struct reset_control *rst;
- spinlock_t global_lock;
- void __iomem *base_addr;
- const struct tegra_dma_chip_data *chip_data;
- const struct tegra_dma_ops *ops;
-
- /*
- * Counter for managing global pausing of the DMA controller.
- * Only applicable for devices that don't support individual
- * channel pausing.
- */
- u32 global_pause_count;
-
- /* Some register need to be cache before suspend */
- u32 reg_gen;
-
- /* Last member of the structure */
- struct tegra_dma_channel channels[0];
-};
-
-static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
-{
- writel(val, tdma->base_addr + reg);
-}
-
-static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
-{
- return readl(tdma->base_addr + reg);
-}
-
-static inline void tdc_write(struct tegra_dma_channel *tdc,
- u32 reg, u32 val)
-{
- writel(val, tdc->chan_addr + reg);
-}
-
-static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
-{
- return readl(tdc->chan_addr + reg);
-}
-
-static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
-{
- return container_of(dc, struct tegra_dma_channel, dma_chan);
-}
-
-static inline struct tegra_dma_desc *txd_to_tegra_dma_desc(
- struct dma_async_tx_descriptor *td)
-{
- return container_of(td, struct tegra_dma_desc, txd);
-}
-
-static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
-{
- return &tdc->dma_chan.dev->device;
-}
-
-static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx);
static int tegra_dma_runtime_suspend(struct device *dev);
static int tegra_dma_runtime_resume(struct device *dev);
-/* Get DMA desc from free list, if not there then allocate it. */
-static struct tegra_dma_desc *tegra_dma_desc_get(
- struct tegra_dma_channel *tdc)
-{
- struct tegra_dma_desc *dma_desc;
- unsigned long flags;
-
- spin_lock_irqsave(&tdc->lock, flags);
-
- /* Do not allocate if desc are waiting for ack */
- list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
- if (async_tx_test_ack(&dma_desc->txd)) {
- list_del(&dma_desc->node);
- spin_unlock_irqrestore(&tdc->lock, flags);
- dma_desc->txd.flags = 0;
- return dma_desc;
- }
- }
-
- spin_unlock_irqrestore(&tdc->lock, flags);
-
- /* Allocate DMA desc */
- dma_desc = kzalloc(sizeof(*dma_desc), GFP_ATOMIC);
- if (!dma_desc) {
- dev_err(tdc2dev(tdc), "dma_desc alloc failed\n");
- return NULL;
- }
-
- dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan);
- dma_desc->txd.tx_submit = tegra_dma_tx_submit;
- dma_desc->txd.flags = 0;
- return dma_desc;
-}
-
-static void tegra_dma_desc_put(struct tegra_dma_channel *tdc,
- struct tegra_dma_desc *dma_desc)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&tdc->lock, flags);
- if (!list_empty(&dma_desc->tx_list))
- list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req);
- list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
- spin_unlock_irqrestore(&tdc->lock, flags);
-}
-
-static struct tegra_dma_sg_req *tegra_dma_sg_req_get(
- struct tegra_dma_channel *tdc)
-{
- struct tegra_dma_sg_req *sg_req = NULL;
- unsigned long flags;
-
- spin_lock_irqsave(&tdc->lock, flags);
- if (!list_empty(&tdc->free_sg_req)) {
- sg_req = list_first_entry(&tdc->free_sg_req,
- typeof(*sg_req), node);
- list_del(&sg_req->node);
- spin_unlock_irqrestore(&tdc->lock, flags);
- return sg_req;
- }
- spin_unlock_irqrestore(&tdc->lock, flags);
-
- sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_ATOMIC);
- if (!sg_req)
- dev_err(tdc2dev(tdc), "sg_req alloc failed\n");
- return sg_req;
-}
-
-static int tegra_dma_slave_config(struct dma_chan *dc,
- struct dma_slave_config *sconfig)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
-
- if (!list_empty(&tdc->pending_sg_req)) {
- dev_err(tdc2dev(tdc), "Configuration not allowed\n");
- return -EBUSY;
- }
-
- memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
- if (!tdc->slave_id)
- tdc->slave_id = sconfig->slave_id;
- tdc->config_init = true;
- return 0;
-}
-
static u32 tegra_dma_get_xfer_count(struct tegra_dma_channel *tdc)
{
u32 wcount;
@@ -409,7 +141,7 @@ static void tegra_dma_global_pause(struct tegra_dma_channel *tdc,
if (tdc->tdma->global_pause_count == 0) {
tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
if (wait_for_burst_complete)
- udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
+ udelay(tdma->chip_data->burst_time);
}
tdc->tdma->global_pause_count++;
@@ -475,7 +207,7 @@ static void tegra_dma_pause(struct tegra_dma_channel *tdc,
tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE,
TEGRA_APBDMA_CHAN_CSRE_PAUSE);
if (wait_for_burst_complete)
- udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
+ udelay(tdma->chip_data->burst_time);
} else {
tegra_dma_global_pause(tdc, wait_for_burst_complete);
}
@@ -529,383 +261,6 @@ static void tegra_dma_start(struct tegra_dma_channel *tdc,
ch_regs->csr | TEGRA_APBDMA_CSR_ENB);
}
-static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *nsg_req)
-{
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- unsigned long status;
-
- /*
- * The DMA controller reloads the new configuration for next transfer
- * after last burst of current transfer completes.
- * If there is no IEC status then this makes sure that last burst
- * has not be completed. There may be case that last burst is on
- * flight and so it can complete but because DMA is paused, it
- * will not generates interrupt as well as not reload the new
- * configuration.
- * If there is already IEC status then interrupt handler need to
- * load new configuration.
- */
- ops->pause(tdc, false);
- status = ops->irq_status(tdc);
-
- /*
- * If interrupt is pending then do nothing as the ISR will handle
- * the programing for new request.
- */
- if (status) {
- dev_err(tdc2dev(tdc),
- "Skipping new configuration as interrupt is pending\n");
- ops->resume(tdc);
- return;
- }
-
- /* Safe to program new configuration */
- ops->program(tdc, nsg_req);
- ops->resume(tdc);
-}
-
-static void tdc_start_head_req(struct tegra_dma_channel *tdc)
-{
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- struct tegra_dma_sg_req *sg_req;
-
- if (list_empty(&tdc->pending_sg_req))
- return;
-
- sg_req = list_first_entry(&tdc->pending_sg_req,
- typeof(*sg_req), node);
- ops->start(tdc, sg_req);
- sg_req->configured = true;
- tdc->busy = true;
-}
-
-static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
-{
- struct tegra_dma_sg_req *hsgreq;
- struct tegra_dma_sg_req *hnsgreq;
-
- if (list_empty(&tdc->pending_sg_req))
- return;
-
- hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
- if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) {
- hnsgreq = list_first_entry(&hsgreq->node,
- typeof(*hnsgreq), node);
- tegra_dma_configure_for_next(tdc, hnsgreq);
- }
-}
-
-static inline int get_current_xferred_count(struct tegra_dma_sg_req *sg_req,
- unsigned long wcount)
-{
- return sg_req->req_len - wcount;
-}
-
-static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
-{
- struct tegra_dma_sg_req *sgreq;
- struct tegra_dma_desc *dma_desc;
-
- while (!list_empty(&tdc->pending_sg_req)) {
- sgreq = list_first_entry(&tdc->pending_sg_req,
- typeof(*sgreq), node);
- list_move_tail(&sgreq->node, &tdc->free_sg_req);
- if (sgreq->last_sg) {
- dma_desc = sgreq->dma_desc;
- dma_desc->dma_status = DMA_ERROR;
- list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
-
- /* Add in cb list if it is not there. */
- if (!dma_desc->cb_count)
- list_add_tail(&dma_desc->cb_node,
- &tdc->cb_desc);
- dma_desc->cb_count++;
- }
- }
- tdc->isr_handler = NULL;
-}
-
-static bool handle_continuous_head_request(struct tegra_dma_channel *tdc,
- struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
-{
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- struct tegra_dma_sg_req *hsgreq = NULL;
-
- if (list_empty(&tdc->pending_sg_req)) {
- dev_err(tdc2dev(tdc), "Dma is running without req\n");
- ops->stop(tdc);
- return false;
- }
-
- /*
- * Check that head req on list should be in flight.
- * If it is not in flight then abort transfer as
- * looping of transfer can not continue.
- */
- hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node);
- if (!hsgreq->configured) {
- ops->stop(tdc);
- dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n");
- tegra_dma_abort_all(tdc);
- return false;
- }
-
- /* Configure next request */
- if (!to_terminate)
- tdc_configure_next_head_desc(tdc);
- return true;
-}
-
-static void handle_once_dma_done(struct tegra_dma_channel *tdc,
- bool to_terminate)
-{
- struct tegra_dma_sg_req *sgreq;
- struct tegra_dma_desc *dma_desc;
-
- tdc->busy = false;
- sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
- dma_desc = sgreq->dma_desc;
- dma_desc->bytes_transferred += sgreq->req_len;
-
- list_del(&sgreq->node);
- if (sgreq->last_sg) {
- dma_desc->dma_status = DMA_COMPLETE;
- dma_cookie_complete(&dma_desc->txd);
- if (!dma_desc->cb_count)
- list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
- dma_desc->cb_count++;
- list_add_tail(&dma_desc->node, &tdc->free_dma_desc);
- }
- list_add_tail(&sgreq->node, &tdc->free_sg_req);
-
- /* Do not start DMA if it is going to be terminate */
- if (to_terminate || list_empty(&tdc->pending_sg_req))
- return;
-
- tdc_start_head_req(tdc);
-}
-
-static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
- bool to_terminate)
-{
- struct tegra_dma_sg_req *sgreq;
- struct tegra_dma_desc *dma_desc;
- bool st;
-
- sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
- dma_desc = sgreq->dma_desc;
- dma_desc->bytes_transferred += sgreq->req_len;
-
- /* Callback need to be call */
- if (!dma_desc->cb_count)
- list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
- dma_desc->cb_count++;
-
- /* If not last req then put at end of pending list */
- if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) {
- list_move_tail(&sgreq->node, &tdc->pending_sg_req);
- sgreq->configured = false;
- st = handle_continuous_head_request(tdc, sgreq, to_terminate);
- if (!st)
- dma_desc->dma_status = DMA_ERROR;
- }
-}
-
-static void tegra_dma_tasklet(unsigned long data)
-{
- struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
- dma_async_tx_callback callback = NULL;
- void *callback_param = NULL;
- struct tegra_dma_desc *dma_desc;
- unsigned long flags;
- int cb_count;
-
- spin_lock_irqsave(&tdc->lock, flags);
- while (!list_empty(&tdc->cb_desc)) {
- dma_desc = list_first_entry(&tdc->cb_desc,
- typeof(*dma_desc), cb_node);
- list_del(&dma_desc->cb_node);
- callback = dma_desc->txd.callback;
- callback_param = dma_desc->txd.callback_param;
- cb_count = dma_desc->cb_count;
- dma_desc->cb_count = 0;
- spin_unlock_irqrestore(&tdc->lock, flags);
- while (cb_count-- && callback)
- callback(callback_param);
- spin_lock_irqsave(&tdc->lock, flags);
- }
- spin_unlock_irqrestore(&tdc->lock, flags);
-}
-
-static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
-{
- struct tegra_dma_channel *tdc = dev_id;
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- unsigned long status;
- unsigned long flags;
-
- spin_lock_irqsave(&tdc->lock, flags);
-
- status = ops->irq_clear(tdc);
- if (status) {
- tdc->isr_handler(tdc, false);
- tasklet_schedule(&tdc->tasklet);
- spin_unlock_irqrestore(&tdc->lock, flags);
- return IRQ_HANDLED;
- }
-
- spin_unlock_irqrestore(&tdc->lock, flags);
- dev_info(tdc2dev(tdc),
- "Interrupt already served status 0x%08lx\n", status);
- return IRQ_NONE;
-}
-
-static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd)
-{
- struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd);
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan);
- unsigned long flags;
- dma_cookie_t cookie;
-
- spin_lock_irqsave(&tdc->lock, flags);
- dma_desc->dma_status = DMA_IN_PROGRESS;
- cookie = dma_cookie_assign(&dma_desc->txd);
- list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req);
- spin_unlock_irqrestore(&tdc->lock, flags);
- return cookie;
-}
-
-static void tegra_dma_issue_pending(struct dma_chan *dc)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- unsigned long flags;
-
- spin_lock_irqsave(&tdc->lock, flags);
- if (list_empty(&tdc->pending_sg_req)) {
- dev_err(tdc2dev(tdc), "No DMA request\n");
- goto end;
- }
- if (!tdc->busy) {
- tdc_start_head_req(tdc);
-
- /* Continuous single mode: Configure next req */
- if (tdc->cyclic) {
- /*
- * Wait for 1 burst time for configure DMA for
- * next transfer.
- */
- udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
- tdc_configure_next_head_desc(tdc);
- }
- }
-end:
- spin_unlock_irqrestore(&tdc->lock, flags);
-}
-
-static int tegra_dma_terminate_all(struct dma_chan *dc)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- struct tegra_dma_sg_req *sgreq;
- struct tegra_dma_desc *dma_desc;
- unsigned long flags;
- unsigned long status;
- unsigned long wcount;
- bool was_busy;
-
- spin_lock_irqsave(&tdc->lock, flags);
- if (list_empty(&tdc->pending_sg_req)) {
- spin_unlock_irqrestore(&tdc->lock, flags);
- return 0;
- }
-
- if (!tdc->busy)
- goto skip_dma_stop;
-
- /* Pause DMA before checking the queue status */
- ops->pause(tdc, true);
-
- status = ops->irq_status(tdc);
- if (status) {
- dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
- tdc->isr_handler(tdc, true);
- }
-
- wcount = ops->get_xfer_count(tdc);
-
- was_busy = tdc->busy;
- ops->stop(tdc);
-
- if (!list_empty(&tdc->pending_sg_req) && was_busy) {
- sgreq = list_first_entry(&tdc->pending_sg_req,
- typeof(*sgreq), node);
- sgreq->dma_desc->bytes_transferred +=
- get_current_xferred_count(sgreq, wcount);
- }
- ops->resume(tdc);
-
-skip_dma_stop:
- tegra_dma_abort_all(tdc);
-
- while (!list_empty(&tdc->cb_desc)) {
- dma_desc = list_first_entry(&tdc->cb_desc,
- typeof(*dma_desc), cb_node);
- list_del(&dma_desc->cb_node);
- dma_desc->cb_count = 0;
- }
- spin_unlock_irqrestore(&tdc->lock, flags);
- return 0;
-}
-
-static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
- dma_cookie_t cookie, struct dma_tx_state *txstate)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- struct tegra_dma_desc *dma_desc;
- struct tegra_dma_sg_req *sg_req;
- enum dma_status ret;
- unsigned long flags;
- unsigned int residual;
-
- ret = dma_cookie_status(dc, cookie, txstate);
- if (ret == DMA_COMPLETE)
- return ret;
-
- spin_lock_irqsave(&tdc->lock, flags);
-
- /* Check on wait_ack desc status */
- list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
- if (dma_desc->txd.cookie == cookie) {
- residual = dma_desc->bytes_requested -
- (dma_desc->bytes_transferred %
- dma_desc->bytes_requested);
- dma_set_residue(txstate, residual);
- ret = dma_desc->dma_status;
- spin_unlock_irqrestore(&tdc->lock, flags);
- return ret;
- }
- }
-
- /* Check in pending list */
- list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
- dma_desc = sg_req->dma_desc;
- if (dma_desc->txd.cookie == cookie) {
- residual = dma_desc->bytes_requested -
- (dma_desc->bytes_transferred %
- dma_desc->bytes_requested);
- dma_set_residue(txstate, residual);
- ret = dma_desc->dma_status;
- spin_unlock_irqrestore(&tdc->lock, flags);
- return ret;
- }
- }
-
- dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie);
- spin_unlock_irqrestore(&tdc->lock, flags);
- return ret;
-}
-
static inline int get_bus_width(struct tegra_dma_channel *tdc,
enum dma_slave_buswidth slave_bw)
{
@@ -1063,259 +418,6 @@ static void tegra_dma_set_xfer_params(struct tegra_dma_channel *tdc,
sg_req->req_len = len;
}
-static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
- struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len,
- enum dma_transfer_direction direction, unsigned long flags,
- void *context)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- struct tegra_dma_desc *dma_desc;
- unsigned int i;
- struct scatterlist *sg;
- struct list_head req_list;
- struct tegra_dma_sg_req sg_base, *sg_req = NULL;
-
- if (!tdc->config_init) {
- dev_err(tdc2dev(tdc), "dma channel is not configured\n");
- return NULL;
- }
- if (sg_len < 1) {
- dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
- return NULL;
- }
-
- if (ops->get_xfer_params_sg(tdc, &sg_base, direction, flags) < 0)
- return NULL;
-
- INIT_LIST_HEAD(&req_list);
-
- dma_desc = tegra_dma_desc_get(tdc);
- if (!dma_desc) {
- dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
- return NULL;
- }
- INIT_LIST_HEAD(&dma_desc->tx_list);
- INIT_LIST_HEAD(&dma_desc->cb_node);
- dma_desc->cb_count = 0;
- dma_desc->bytes_requested = 0;
- dma_desc->bytes_transferred = 0;
- dma_desc->dma_status = DMA_IN_PROGRESS;
-
- /* Make transfer requests */
- for_each_sg(sgl, sg, sg_len, i) {
- u32 len, mem;
-
- mem = sg_dma_address(sg);
- len = sg_dma_len(sg);
-
- if ((len & 3) || (mem & 3) ||
- (len > tdc->tdma->chip_data->max_dma_count)) {
- dev_err(tdc2dev(tdc),
- "Dma length/memory address is not supported\n");
- tegra_dma_desc_put(tdc, dma_desc);
- return NULL;
- }
-
- sg_req = tegra_dma_sg_req_get(tdc);
- if (!sg_req) {
- dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
- tegra_dma_desc_put(tdc, dma_desc);
- return NULL;
- }
-
- dma_desc->bytes_requested += len;
-
- ops->set_xfer_params(tdc, sg_req, &sg_base, direction, mem,
- len);
- sg_req->dma_desc = dma_desc;
-
- list_add_tail(&sg_req->node, &dma_desc->tx_list);
- }
- sg_req->last_sg = true;
- if (flags & DMA_CTRL_ACK)
- dma_desc->txd.flags = DMA_CTRL_ACK;
-
- /*
- * Make sure that mode should not be conflicting with currently
- * configured mode.
- */
- if (!tdc->isr_handler) {
- tdc->isr_handler = handle_once_dma_done;
- tdc->cyclic = false;
- } else {
- if (tdc->cyclic) {
- dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n");
- tegra_dma_desc_put(tdc, dma_desc);
- return NULL;
- }
- }
-
- return &dma_desc->txd;
-}
-
-static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
- struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
- size_t period_len, enum dma_transfer_direction direction,
- unsigned long flags)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- const struct tegra_dma_ops *ops = tdc->tdma->ops;
- struct tegra_dma_desc *dma_desc = NULL;
- struct tegra_dma_sg_req sg_base, *sg_req = NULL;
- int len;
- size_t remain_len;
- dma_addr_t mem = buf_addr;
-
- if (!buf_len || !period_len) {
- dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
- return NULL;
- }
-
- if (!tdc->config_init) {
- dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
- return NULL;
- }
-
- /*
- * We allow to take more number of requests till DMA is
- * not started. The driver will loop over all requests.
- * Once DMA is started then new requests can be queued only after
- * terminating the DMA.
- */
- if (tdc->busy) {
- dev_err(tdc2dev(tdc), "Request not allowed when dma running\n");
- return NULL;
- }
-
- /*
- * We only support cycle transfer when buf_len is multiple of
- * period_len.
- */
- if (buf_len % period_len) {
- dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
- return NULL;
- }
-
- len = period_len;
- if ((len & 3) || (buf_addr & 3) ||
- (len > tdc->tdma->chip_data->max_dma_count)) {
- dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
- return NULL;
- }
-
- if (ops->get_xfer_params_cyclic(tdc, &sg_base, direction, flags) < 0)
- return NULL;
-
- dma_desc = tegra_dma_desc_get(tdc);
- if (!dma_desc) {
- dev_err(tdc2dev(tdc), "not enough descriptors available\n");
- return NULL;
- }
-
- INIT_LIST_HEAD(&dma_desc->tx_list);
- INIT_LIST_HEAD(&dma_desc->cb_node);
- dma_desc->cb_count = 0;
-
- dma_desc->bytes_transferred = 0;
- dma_desc->bytes_requested = buf_len;
- remain_len = buf_len;
-
- /* Split transfer equal to period size */
- while (remain_len) {
- sg_req = tegra_dma_sg_req_get(tdc);
- if (!sg_req) {
- dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
- tegra_dma_desc_put(tdc, dma_desc);
- return NULL;
- }
-
- ops->set_xfer_params(tdc, sg_req, &sg_base, direction, mem,
- len);
- sg_req->dma_desc = dma_desc;
-
- list_add_tail(&sg_req->node, &dma_desc->tx_list);
- remain_len -= len;
- mem += len;
- }
- sg_req->last_sg = true;
- if (flags & DMA_CTRL_ACK)
- dma_desc->txd.flags = DMA_CTRL_ACK;
-
- /*
- * Make sure that mode should not be conflicting with currently
- * configured mode.
- */
- if (!tdc->isr_handler) {
- tdc->isr_handler = handle_cont_sngl_cycle_dma_done;
- tdc->cyclic = true;
- } else {
- if (!tdc->cyclic) {
- dev_err(tdc2dev(tdc), "DMA configuration conflict\n");
- tegra_dma_desc_put(tdc, dma_desc);
- return NULL;
- }
- }
-
- return &dma_desc->txd;
-}
-
-static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- struct tegra_dma *tdma = tdc->tdma;
-
- dma_cookie_init(&tdc->dma_chan);
- tdc->config_init = false;
-
- return pm_runtime_get_sync(tdma->dev);
-}
-
-static void tegra_dma_free_chan_resources(struct dma_chan *dc)
-{
- struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
- struct tegra_dma *tdma = tdc->tdma;
-
- struct tegra_dma_desc *dma_desc;
- struct tegra_dma_sg_req *sg_req;
- struct list_head dma_desc_list;
- struct list_head sg_req_list;
- unsigned long flags;
-
- INIT_LIST_HEAD(&dma_desc_list);
- INIT_LIST_HEAD(&sg_req_list);
-
- dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
-
- if (tdc->busy)
- tegra_dma_terminate_all(dc);
-
- spin_lock_irqsave(&tdc->lock, flags);
- list_splice_init(&tdc->pending_sg_req, &sg_req_list);
- list_splice_init(&tdc->free_sg_req, &sg_req_list);
- list_splice_init(&tdc->free_dma_desc, &dma_desc_list);
- INIT_LIST_HEAD(&tdc->cb_desc);
- tdc->config_init = false;
- tdc->isr_handler = NULL;
- spin_unlock_irqrestore(&tdc->lock, flags);
-
- while (!list_empty(&dma_desc_list)) {
- dma_desc = list_first_entry(&dma_desc_list,
- typeof(*dma_desc), node);
- list_del(&dma_desc->node);
- kfree(dma_desc);
- }
-
- while (!list_empty(&sg_req_list)) {
- sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node);
- list_del(&sg_req->node);
- kfree(sg_req);
- }
- pm_runtime_put(tdma->dev);
-
- tdc->slave_id = 0;
-}
-
static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
@@ -1335,6 +437,7 @@ static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
/* Tegra20 specific DMA controller information */
static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
+ .burst_time = TEGRA_APBDMA_BURST_COMPLETE_TIME,
.nr_channels = 16,
.channel_reg_size = 0x20,
.max_dma_count = 1024UL * 64,
@@ -1344,6 +447,7 @@ static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
/* Tegra30 specific DMA controller information */
static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
+ .burst_time = TEGRA_APBDMA_BURST_COMPLETE_TIME,
.nr_channels = 32,
.channel_reg_size = 0x20,
.max_dma_count = 1024UL * 64,
@@ -1353,6 +457,7 @@ static const struct tegra_dma_chip_data tegra30_dma_chip_data = {
/* Tegra114 specific DMA controller information */
static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
+ .burst_time = TEGRA_APBDMA_BURST_COMPLETE_TIME,
.nr_channels = 32,
.channel_reg_size = 0x20,
.max_dma_count = 1024UL * 64,
@@ -1362,6 +467,7 @@ static const struct tegra_dma_chip_data tegra114_dma_chip_data = {
/* Tegra148 specific DMA controller information */
static const struct tegra_dma_chip_data tegra148_dma_chip_data = {
+ .burst_time = TEGRA_APBDMA_BURST_COMPLETE_TIME,
.nr_channels = 32,
.channel_reg_size = 0x40,
.max_dma_count = 1024UL * 64,
--
2.1.4
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