[PATCH v6 1/3] dmaengine: Add support for APM X-Gene SoC DMA engine driver
From: Rameshwar Prasad Sahu
Date: Tue Feb 24 2015 - 07:55:39 EST
This patch implements the APM X-Gene SoC DMA engine driver. The APM X-Gene
SoC DMA engine consists of 4 DMA channels for performing DMA operations.
These DMA operations include memory copy and scatter-gather memory copy
offloading.
Signed-off-by: Rameshwar Prasad Sahu <rsahu@xxxxxxx>
Signed-off-by: Loc Ho <lho@xxxxxxx>
---
drivers/dma/Kconfig | 8 +
drivers/dma/Makefile | 1 +
drivers/dma/xgene-dma.c | 1738 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1747 insertions(+)
create mode 100755 drivers/dma/xgene-dma.c
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index a874b6e..0e05831 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -425,6 +425,14 @@ config IMG_MDC_DMA
help
Enable support for the IMG multi-threaded DMA controller (MDC).
+config XGENE_DMA
+ tristate "APM X-Gene DMA support"
+ depends on ARCH_XGENE
+ select DMA_ENGINE
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
+ help
+ Enable support for the APM X-Gene SoC DMA engine.
+
config DMA_ENGINE
bool
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index f915f61..06c1576 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -51,3 +51,4 @@ obj-$(CONFIG_INTEL_MIC_X100_DMA) += mic_x100_dma.o
obj-$(CONFIG_NBPFAXI_DMA) += nbpfaxi.o
obj-$(CONFIG_DMA_SUN6I) += sun6i-dma.o
obj-$(CONFIG_IMG_MDC_DMA) += img-mdc-dma.o
+obj-$(CONFIG_XGENE_DMA) += xgene-dma.o
diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c
new file mode 100755
index 0000000..e736c2e
--- /dev/null
+++ b/drivers/dma/xgene-dma.c
@@ -0,0 +1,1738 @@
+/*
+ * Applied Micro X-Gene SoC DMA engine Driver
+ *
+ * Copyright (c) 2015, Applied Micro Circuits Corporation
+ * Authors: Rameshwar Prasad Sahu <rsahu@xxxxxxx>
+ * Loc Ho <lho@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that 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/>.
+ *
+ * NOTE: PM support is currently not available.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+#include "dmaengine.h"
+
+/* DMA ring csr registers and bit definations */
+#define DMA_RING_CONFIG 0x04
+#define DMA_RING_ENABLE BIT(31)
+#define DMA_RING_ID 0x08
+#define DMA_RING_ID_SETUP(v) ((v) | BIT(31))
+#define DMA_RING_ID_BUF 0x0C
+#define DMA_RING_ID_BUF_SETUP(v) (((v) << 9) | BIT(21))
+#define DMA_RING_THRESLD0_SET1 0x30
+#define DMA_RING_THRESLD0_SET1_VAL 0X64
+#define DMA_RING_THRESLD1_SET1 0x34
+#define DMA_RING_THRESLD1_SET1_VAL 0xC8
+#define DMA_RING_HYSTERESIS 0x68
+#define DMA_RING_HYSTERESIS_VAL 0xFFFFFFFF
+#define DMA_RING_STATE 0x6C
+#define DMA_RING_STATE_WR_BASE 0x70
+#define DMA_RING_NE_INT_MODE 0x017C
+#define DMA_RING_NE_INT_MODE_SET(m, v) \
+ ((m) = ((m) & ~BIT(31 - (v))) | BIT(31 - (v)))
+#define DMA_RING_NE_INT_MODE_RESET(m, v) \
+ ((m) &= (~BIT(31 - (v))))
+#define DMA_RING_CLKEN 0xC208
+#define DMA_RING_SRST 0xC200
+#define DMA_RING_MEM_RAM_SHUTDOWN 0xD070
+#define DMA_RING_BLK_MEM_RDY 0xD074
+#define DMA_RING_BLK_MEM_RDY_VAL 0xFFFFFFFF
+#define DMA_RING_DESC_CNT(v) (((v) & 0x0001FFFE) >> 1)
+#define DMA_RING_ID_GET(owner, num) (((owner) << 6) | (num))
+#define DMA_RING_DST_ID(v) ((1 << 10) | (v))
+#define DMA_RING_CMD_OFFSET 0x2C
+#define DMA_RING_CMD_BASE_OFFSET(v) ((v) << 6)
+#define DMA_RING_COHERENT_SET(m) (((u32 *)(m))[2] |= BIT(4))
+#define DMA_RING_ADDRL_SET(m, v) (((u32 *)(m))[2] |= (((v) >> 8) << 5))
+#define DMA_RING_ADDRH_SET(m, v) (((u32 *)(m))[3] |= ((v) >> 35))
+#define DMA_RING_ACCEPTLERR_SET(m) (((u32 *)(m))[3] |= BIT(19))
+#define DMA_RING_SIZE_SET(m, v) (((u32 *)(m))[3] |= ((v) << 23))
+#define DMA_RING_RECOMBBUF_SET(m) (((u32 *)(m))[3] |= BIT(27))
+#define DMA_RING_RECOMTIMEOUTL_SET(m) (((u32 *)(m))[3] |= (0x7 << 28))
+#define DMA_RING_RECOMTIMEOUTH_SET(m) (((u32 *)(m))[4] |= 0x3)
+#define DMA_RING_SELTHRSH_SET(m) (((u32 *)(m))[4] |= BIT(3))
+#define DMA_RING_TYPE_SET(m, v) (((u32 *)(m))[4] |= ((v) << 19))
+
+/* DMA device csr registers and bit definitions */
+#define DMA_IPBRR 0x0
+#define DMA_DEV_ID_RD(v) ((v) & 0x00000FFF)
+#define DMA_BUS_ID_RD(v) (((v) >> 12) & 3)
+#define DMA_REV_NO_RD(v) (((v) >> 14) & 3)
+#define DMA_GCR 0x10
+#define DMA_CH_SETUP(v) ((v) = ((v) & ~0x000FFFFF) | 0x000AAFFF)
+#define DMA_ENABLE(v) ((v) |= BIT(31))
+#define DMA_DISABLE(v) ((v) &= ~BIT(31))
+#define DMA_INT 0x70
+#define DMA_INT_MASK 0x74
+#define DMA_INT_ALL_MASK 0xFFFFFFFF
+#define DMA_INT_ALL_UNMASK 0x0
+#define DMA_INT_MASK_SHIFT 0x14
+#define DMA_RING_INT0_MASK 0x90A0
+#define DMA_RING_INT1_MASK 0x90A8
+#define DMA_RING_INT2_MASK 0x90B0
+#define DMA_RING_INT3_MASK 0x90B8
+#define DMA_RING_INT4_MASK 0x90C0
+#define DMA_CFG_RING_WQ_ASSOC 0x90E0
+#define DMA_ASSOC_RING_MNGR1 0xFFFFFFFF
+#define DMA_MEM_RAM_SHUTDOWN 0xD070
+#define DMA_BLK_MEM_RDY 0xD074
+#define DMA_BLK_MEM_RDY_VAL 0xFFFFFFFF
+
+/* DMA Descriptor format */
+#define DMA_DESC_ELERR_RD(m) (((m) >> 46) & 0x3)
+#define DMA_DESC_NV_SET(m) (((u64 *)(m))[0] |= BIT_ULL(50))
+#define DMA_DESC_IN_SET(m) (((u64 *)(m))[0] |= BIT_ULL(55))
+#define DMA_DESC_RTYPE_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 56))
+#define DMA_DESC_LERR_RD(m) (((m) >> 60) & 0x7)
+#define DMA_DESC_BUFADDR_SET(m, v) (((u64 *)(m))[0] |= (v))
+#define DMA_DESC_BUFLEN_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 48))
+#define DMA_DESC_C_SET(m) (((u64 *)(m))[1] |= BIT_ULL(63))
+#define DMA_DESC_DR_SET(m) (((u64 *)(m))[2] |= BIT_ULL(61))
+#define DMA_DESC_DST_ADDR_SET(m, v) (((u64 *)(m))[3] |= (v))
+#define DMA_DESC_H0ENQ_NUM_SET(m, v) (((u64 *)(m))[3] |= ((u64)(v) << 48))
+#define DMA_DESC_STATUS(x, y) (((x) << 4) | (y))
+
+/* DMA descriptor empty s/w signature */
+#define DMA_DESC_EMPTY_INDEX 0
+#define DMA_DESC_EMPTY_SIGNATURE ~0ULL
+#define DMA_DESC_SET_EMPTY(m) \
+ (((u64 *)(m))[DMA_DESC_EMPTY_INDEX] = DMA_DESC_EMPTY_SIGNATURE)
+#define DMA_DESC_IS_EMPTY(m) \
+ (((u64 *)(m))[DMA_DESC_EMPTY_INDEX] == DMA_DESC_EMPTY_SIGNATURE)
+
+/* DMA configurable parameters defines */
+#define DMA_RING_NUM 512
+#define DMA_BUFNUM 0x0
+#define DMA_CPU_BUFNUM 0x18
+#define DMA_RING_OWNER_DMA 0x03
+#define DMA_RING_OWNER_CPU 0x0F
+#define DMA_RING_TYPE_REGULAR 0x01
+#define DMA_RING_WQ_DESC_SIZE 32
+#define DMA_RING_NUM_CONFIG 5
+#define DMA_MAX_CHANNEL 4
+#define DMA_MAX_BYTE_CNT 0x4000 /* 16 KB */
+#define DMA_MAX_64B_DESC_BYTE_CNT 0x14000 /* 80 KB */
+#define DMA_16K_BUFFER_LEN_CODE 0x0
+#define DMA_INVALID_LEN_CODE 0x7800
+
+/* DMA descriptor error codes */
+#define ERR_DESC_AXI 0x01
+#define ERR_BAD_DESC 0x02
+#define ERR_READ_DATA_AXI 0x03
+#define ERR_WRITE_DATA_AXI 0x04
+#define ERR_FBP_TIMEOUT 0x05
+#define ERR_ECC 0x06
+#define ERR_DIFF_SIZE 0x08
+#define ERR_SCT_GAT_LEN 0x09
+#define ERR_CRC_ERR 0x11
+#define ERR_CHKSUM 0x12
+#define ERR_DIF 0x13
+
+/* DMA error interrupt codes */
+#define ERR_DIF_SIZE_INT 0x0
+#define ERR_GS_ERR_INT 0x1
+#define ERR_FPB_TIMEO_INT 0x2
+#define ERR_WFIFO_OVF_INT 0x3
+#define ERR_RFIFO_OVF_INT 0x4
+#define ERR_WR_TIMEO_INT 0x5
+#define ERR_RD_TIMEO_INT 0x6
+#define ERR_WR_ERR_INT 0x7
+#define ERR_RD_ERR_INT 0x8
+#define ERR_BAD_DESC_INT 0x9
+#define ERR_DESC_DST_INT 0xA
+#define ERR_DESC_SRC_INT 0xB
+
+/* Define to dump DMA descriptor */
+#define DMA_DESC_ERR_DUMP(desc) \
+ print_hex_dump(KERN_ERR, "X-Gene DMA: Rx ERR DESC ", \
+ DUMP_PREFIX_ADDRESS, 16, 8, (desc), 32, 0)
+
+#define to_dma_desc_sw(tx) \
+ container_of(tx, struct xgene_dma_desc_sw, tx)
+#define to_dma_chan(dchan) \
+ container_of(dchan, struct xgene_dma_chan, dma_chan)
+
+#define chan_dbg(chan, fmt, arg...) \
+ dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg)
+#define chan_err(chan, fmt, arg...) \
+ dev_err(chan->dev, "%s: " fmt, chan->name, ##arg)
+
+struct xgene_dma_desc_hw {
+ u64 m0;
+ u64 m1;
+ u64 m2;
+ u64 m3;
+};
+
+enum xgene_dma_ring_cfgsize {
+ DMA_RING_CFG_SIZE_512B,
+ DMA_RING_CFG_SIZE_2KB,
+ DMA_RING_CFG_SIZE_16KB,
+ DMA_RING_CFG_SIZE_64KB,
+ DMA_RING_CFG_SIZE_512KB,
+ DMA_RING_CFG_SIZE_INVALID
+};
+
+struct xgene_dma_ring {
+ struct xgene_dma *pdma;
+ u8 buf_num;
+ u16 id;
+ u16 num;
+ u16 head;
+ u16 owner;
+ u16 slots;
+ u16 dst_ring_num;
+ u32 size;
+ void __iomem *cmd;
+ void __iomem *cmd_base;
+ dma_addr_t desc_paddr;
+ u32 state[DMA_RING_NUM_CONFIG];
+ enum xgene_dma_ring_cfgsize cfgsize;
+ union {
+ void *desc_vaddr;
+ struct xgene_dma_desc_hw *desc_hw;
+ };
+};
+
+struct xgene_dma_desc_sw {
+ struct xgene_dma_desc_hw desc1;
+ struct xgene_dma_desc_hw desc2;
+ u8 desc_cnt;
+ struct list_head node;
+ struct list_head tx_list;
+ struct dma_async_tx_descriptor tx;
+};
+
+/**
+ * struct xgene_dma_chan - internal representation of an DMA channel
+ * @dma_chan: dmaengine channel object member
+ * @pdma: DMA device structure reference
+ * @dev: struct device reference for dma mapping api
+ * @id: raw id of this channel
+ * @rx_irq: channel IRQ
+ * @name: name of DMA channel
+ * @lock: serializes enqueue/dequeue operations to the descriptor pool
+ * @pending: number of transaction request pushed to DMA controller for
+ * execution, but still waiting for completion,
+ * @ld_pending: descriptors which are queued to run, but have not yet been
+ * submitted to the hardware for execution
+ * @ld_running: descriptors which are currently being executing by the hardware
+ * @ld_completed: descriptors which have finished execution by the hardware.
+ * These descriptors have already had their cleanup actions run. They
+ * are waiting for the ACK bit to be set by the async tx API.
+ * @desc_pool: descriptor pool for DMA operations
+ * @tasklet: bottom half where all completed descriptors cleans
+ * @tx_ring: transmit ring descriptor that we use to prepare actual
+ * descriptors for further executions
+ * @rx_ring: receive ring descriptor that we use to get completed DMA
+ * descriptors during cleanup time
+ */
+struct xgene_dma_chan {
+ struct dma_chan dma_chan;
+ struct xgene_dma *pdma;
+ struct device *dev;
+ int id;
+ int rx_irq;
+ char name[8];
+ spinlock_t lock;
+ int pending;
+ struct list_head ld_pending;
+ struct list_head ld_running;
+ struct list_head ld_completed;
+ struct dma_pool *desc_pool;
+ struct tasklet_struct tasklet;
+ struct xgene_dma_ring tx_ring;
+ struct xgene_dma_ring rx_ring;
+};
+
+/**
+ * struct xgene_dma - internal representation of an DMA device
+ * @err_irq: DMA error irq number
+ * @ring_num: start id number for DMA ring
+ * @csr_dma: base for DMA register access
+ * @csr_ring: base for DMA ring register access
+ * @csr_ring_cmd: base for DMA ring command register access
+ * @dma_dev: embedded struct dma_device
+ * @chan: reference to DMA channels
+ */
+struct xgene_dma {
+ struct device *dev;
+ struct clk *clk;
+ int err_irq;
+ int ring_num;
+ void __iomem *csr_dma;
+ void __iomem *csr_ring;
+ void __iomem *csr_ring_cmd;
+ struct dma_device dma_dev[DMA_MAX_CHANNEL];
+ struct xgene_dma_chan chan[DMA_MAX_CHANNEL];
+};
+
+static const char * const xgene_dma_desc_hw_err[] = {
+ [ERR_DESC_AXI] = "AXI error when reading src/dst link list",
+ [ERR_BAD_DESC] = "ERR or El_ERR fields not set to zero in desc",
+ [ERR_READ_DATA_AXI] = "AXI error when reading data",
+ [ERR_WRITE_DATA_AXI] = "AXI error when writing data",
+ [ERR_FBP_TIMEOUT] = "Timeout on bufpool fetch",
+ [ERR_ECC] = "ECC double bit error",
+ [ERR_DIFF_SIZE] = "Bufpool too small to hold all the DIF result",
+ [ERR_SCT_GAT_LEN] = "Gather and scatter data length not same",
+ [ERR_CRC_ERR] = "CRC error",
+ [ERR_CHKSUM] = "Checksum error",
+ [ERR_DIF] = "DIF error",
+};
+
+static const char * const xgene_dma_err[] = {
+ [ERR_DIF_SIZE_INT] = "DIF size error",
+ [ERR_GS_ERR_INT] = "Gather scatter not same size error",
+ [ERR_FPB_TIMEO_INT] = "Free pool time out error",
+ [ERR_WFIFO_OVF_INT] = "Write FIFO over flow error",
+ [ERR_RFIFO_OVF_INT] = "Read FIFO over flow error",
+ [ERR_WR_TIMEO_INT] = "Write time out error",
+ [ERR_RD_TIMEO_INT] = "Read time out error",
+ [ERR_WR_ERR_INT] = "HBF bus write error",
+ [ERR_RD_ERR_INT] = "HBF bus read error",
+ [ERR_BAD_DESC_INT] = "Ring descriptor HE0 not set error",
+ [ERR_DESC_DST_INT] = "HFB reading dst link address error",
+ [ERR_DESC_SRC_INT] = "HFB reading src link address error",
+};
+
+static void xgene_dma_cpu_to_le64(u64 *desc, int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++)
+ desc[i] = cpu_to_le64(desc[i]);
+}
+
+static u16 xgene_dma_encode_len(u32 len)
+{
+ return (len < DMA_MAX_BYTE_CNT) ?
+ len : DMA_16K_BUFFER_LEN_CODE;
+}
+
+static u32 xgene_dma_ring_desc_cnt(struct xgene_dma_ring *ring)
+{
+ u32 __iomem *cmd_base = ring->cmd_base;
+ u32 ring_state = ioread32(&cmd_base[1]);
+
+ return DMA_RING_DESC_CNT(ring_state);
+}
+
+static void xgene_dma_set_src_buffer(void *ext8, size_t *len,
+ dma_addr_t *paddr)
+{
+ size_t nbytes = (*len < DMA_MAX_BYTE_CNT) ?
+ *len : DMA_MAX_BYTE_CNT;
+
+ DMA_DESC_BUFADDR_SET(ext8, *paddr);
+ DMA_DESC_BUFLEN_SET(ext8, xgene_dma_encode_len(*len));
+ *len -= nbytes;
+ *paddr += nbytes;
+}
+
+static void xgene_dma_invalidate_buffer(void *ext8)
+{
+ DMA_DESC_BUFLEN_SET(ext8, DMA_INVALID_LEN_CODE);
+}
+
+static void *xgene_dma_lookup_ext8(u64 *desc, int idx)
+{
+ return (idx % 2) ? (desc + idx - 1) : (desc + idx + 1);
+}
+
+static void xgene_dma_init_desc(void *desc, u16 dst_ring_num)
+{
+ DMA_DESC_C_SET(desc); /* Coherent IO */
+ DMA_DESC_IN_SET(desc);
+ DMA_DESC_DR_SET(desc);
+ DMA_DESC_RTYPE_SET(desc, DMA_RING_OWNER_DMA);
+ DMA_DESC_H0ENQ_NUM_SET(desc, dst_ring_num);
+}
+
+static void xgene_dma_prep_cpy_desc(struct xgene_dma_chan *chan,
+ struct xgene_dma_desc_sw *desc_sw,
+ dma_addr_t dst, dma_addr_t src,
+ size_t len)
+{
+ struct xgene_dma_ring *ring = &chan->tx_ring;
+ void *desc1, *desc2;
+ int i;
+
+ /* Get 1st descriptor */
+ desc1 = &desc_sw->desc1;
+ xgene_dma_init_desc(desc1, ring->dst_ring_num);
+ DMA_DESC_DST_ADDR_SET(desc1, dst);
+
+ /* Set 1st source address */
+ xgene_dma_set_src_buffer(desc1 + 8, &len, &src);
+
+ if (len <= 0) {
+ desc2 = NULL;
+ desc_sw->desc_cnt = 1;
+ goto skip_additional_src;
+ }
+
+ /*
+ * We need to split this source buffer,
+ * and need to use 2nd descriptor
+ */
+ desc2 = &desc_sw->desc2;
+ DMA_DESC_NV_SET(desc1);
+
+ /* Set 2nd to 5th source address */
+ for (i = 0; i < 4 && len; i++)
+ xgene_dma_set_src_buffer(xgene_dma_lookup_ext8(desc2, i),
+ &len, &src);
+
+ /* Invalidate unused source address field */
+ for (; i < 4; i++)
+ xgene_dma_invalidate_buffer(xgene_dma_lookup_ext8(desc2, i));
+
+ desc_sw->desc_cnt = 2;
+
+skip_additional_src:
+ /* Hardware stores descriptor in little endian format */
+ xgene_dma_cpu_to_le64(desc1, 4);
+ if (desc2)
+ xgene_dma_cpu_to_le64(desc2, 4);
+}
+
+static dma_cookie_t xgene_dma_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct xgene_dma_desc_sw *desc;
+ struct xgene_dma_chan *chan;
+ dma_cookie_t cookie;
+
+ if (unlikely(!tx))
+ return -EINVAL;
+
+ chan = to_dma_chan(tx->chan);
+ desc = to_dma_desc_sw(tx);
+
+ spin_lock_bh(&chan->lock);
+
+ cookie = dma_cookie_assign(tx);
+
+ /* Add this transaction list onto the tail of the pending queue */
+ list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
+
+ spin_unlock_bh(&chan->lock);
+
+ return cookie;
+}
+
+static void xgene_dma_free_descriptor(struct xgene_dma_chan *chan,
+ struct xgene_dma_desc_sw *desc)
+{
+ list_del(&desc->node);
+ chan_dbg(chan, "LD %p free\n", desc);
+ dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
+}
+
+static struct xgene_dma_desc_sw *xgene_dma_alloc_descriptor(
+ struct xgene_dma_chan *chan)
+{
+ struct xgene_dma_desc_sw *desc;
+ dma_addr_t phys;
+
+ desc = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, &phys);
+ if (!desc) {
+ chan_dbg(chan, "Failed to allocate LDs\n");
+ return NULL;
+ }
+
+ memset(desc, 0, sizeof(*desc));
+
+ INIT_LIST_HEAD(&desc->tx_list);
+ desc->tx.phys = phys;
+ desc->tx.tx_submit = xgene_dma_tx_submit;
+ dma_async_tx_descriptor_init(&desc->tx, &chan->dma_chan);
+
+ chan_dbg(chan, "LD %p allocated\n", desc);
+
+ return desc;
+}
+
+/**
+ * xgene_dma_clean_completed_descriptor - free all descriptors which
+ * has been completed and acked
+ * @chan: DMA channel
+ *
+ * This function is used on all completed and acked descriptors.
+ * All descriptors should only be freed in this function.
+ */
+static void xgene_dma_clean_completed_descriptor(struct xgene_dma_chan *chan)
+{
+ struct xgene_dma_desc_sw *desc, *_desc;
+
+ /* Run the callback for each descriptor, in order */
+ list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) {
+ if (async_tx_test_ack(&desc->tx))
+ xgene_dma_free_descriptor(chan, desc);
+ }
+}
+
+/**
+ * xgene_dma_run_tx_complete_actions - cleanup a single link descriptor
+ * @chan: DMA channel
+ * @desc: descriptor to cleanup and free
+ *
+ * This function is used on a descriptor which has been executed by the DMA
+ * controller. It will run any callbacks, submit any dependencies.
+ */
+static void xgene_dma_run_tx_complete_actions(struct xgene_dma_chan *chan,
+ struct xgene_dma_desc_sw *desc)
+{
+ struct dma_async_tx_descriptor *tx = &desc->tx;
+
+ if (tx->cookie == 0)
+ return;
+
+ dma_cookie_complete(tx);
+
+ /* Run the link descriptor callback function */
+ if (tx->callback)
+ tx->callback(tx->callback_param);
+
+ dma_descriptor_unmap(tx);
+
+ /* Run any dependencies */
+ dma_run_dependencies(tx);
+}
+
+/**
+ * xgene_dma_clean_running_descriptor - move the completed descriptor from
+ * ld_running to ld_completed
+ * @chan: DMA channel
+ * @desc: the descriptor which is completed
+ *
+ * Free the descriptor directly if acked by async_tx api, or move it to
+ * queue ld_completed.
+ */
+static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan,
+ struct xgene_dma_desc_sw *desc)
+{
+ /* Remove from the list of transactions */
+ list_del(&desc->node);
+
+ /*
+ * the client is allowed to attach dependent operations
+ * until 'ack' is set
+ */
+ if (!async_tx_test_ack(&desc->tx)) {
+ /*
+ * Move this descriptor to the list of descriptors which is
+ * completed, but still awaiting the 'ack' bit to be set.
+ */
+ list_add_tail(&desc->node, &chan->ld_completed);
+ return;
+ }
+
+ chan_dbg(chan, "LD %p free\n", desc);
+ dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
+}
+
+/**
+ * xgene_chan_xfer_ld_pending - push any pending transactions to hw
+ * @chan : DMA channel
+ *
+ * LOCKING: must hold chan->desc_lock
+ */
+static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
+{
+ struct xgene_dma_ring *ring = &chan->tx_ring;
+ struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
+ struct xgene_dma_desc_hw *desc_hw;
+
+ /*
+ * If the list of pending descriptors is empty, then we
+ * don't need to do any work at all
+ */
+ if (list_empty(&chan->ld_pending)) {
+ chan_dbg(chan, "No pending LDs\n");
+ return;
+ }
+
+ /*
+ * Move elements from the queue of pending transactions onto the list
+ * of running transactions and push it to hw for further executions
+ */
+
+ list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) {
+ /*
+ * Check if have pushed max number of transactions to hw
+ * as capable, so let's stop here and will push remaining
+ * elements from pening ld queue after completing some
+ * descriptors that we have already pushed
+ */
+ if ((chan->pending >= ring->slots) ||
+ (xgene_dma_ring_desc_cnt(ring) > (ring->slots - 2)))
+ break;
+
+ /* Get hw descriptor from DMA tx ring */
+ desc_hw = &ring->desc_hw[ring->head];
+
+ /*
+ * Increment the head count to point next
+ * descriptor for next time
+ */
+ if (++ring->head == ring->slots)
+ ring->head = 0;
+
+ /* Copy prepared sw descriptor data to hw descriptor */
+ memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw));
+
+ /*
+ * Check if we have prepared 64B descriptor,
+ * in this case we need one more hw descriptor
+ */
+ if (desc_sw->desc_cnt == 2) {
+ desc_hw = &ring->desc_hw[ring->head];
+
+ if (++ring->head == ring->slots)
+ ring->head = 0;
+
+ memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
+ }
+
+ /*
+ * Delete this element from ld pending queue and append it to
+ * ld running queue
+ */
+ list_move_tail(&desc_sw->node, &chan->ld_running);
+
+ /* Increment the pending transaction count */
+ chan->pending++;
+
+ /* Notify the hw that we have descriptor ready for execution */
+ iowrite32(desc_sw->desc_cnt, ring->cmd);
+ }
+}
+
+/**
+ * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed
+ * and move them to ld_completed to free until flag 'ack' is set
+ * @chan: DMA channel
+ *
+ * This function is used on descriptors which have been executed by the DMA
+ * controller. It will run any callbacks, submit any dependencies, then
+ * free these descriptors if flag 'ack' is set.
+ */
+static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan)
+{
+ struct xgene_dma_ring *ring = &chan->rx_ring;
+ struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
+ struct xgene_dma_desc_hw *desc_hw;
+ u8 status;
+
+ /* Clean already completed and acked descriptors */
+ xgene_dma_clean_completed_descriptor(chan);
+
+ /* Run the callback for each descriptor, in order */
+ list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) {
+ /* Get subsequent hw descriptor from DMA rx ring */
+ desc_hw = &ring->desc_hw[ring->head];
+
+ /* Check if this descriptor has been completed */
+ if (unlikely(DMA_DESC_IS_EMPTY(desc_hw)))
+ break;
+
+ if (++ring->head == ring->slots)
+ ring->head = 0;
+
+ /* Check if we have any error with DMA transactions */
+ status = DMA_DESC_STATUS(
+ DMA_DESC_ELERR_RD(le64_to_cpu(desc_hw->m0)),
+ DMA_DESC_LERR_RD(le64_to_cpu(desc_hw->m0)));
+ if (status) {
+ chan_err(chan, "%s\n", xgene_dma_desc_hw_err[status]);
+ DMA_DESC_ERR_DUMP(desc_hw);
+ }
+
+ /* Notify the hw about this completed descriptor */
+ iowrite32(-1, ring->cmd);
+
+ /* Mark this hw descriptor as processed */
+ DMA_DESC_SET_EMPTY(desc_hw);
+
+ xgene_dma_run_tx_complete_actions(chan, desc_sw);
+
+ xgene_dma_clean_running_descriptor(chan, desc_sw);
+
+ /*
+ * Decrement the pending transaction count
+ * as we have processed one
+ */
+ chan->pending--;
+ }
+
+ /*
+ * Start any pending transactions automatically
+ *
+ * In the ideal case, we keep the DMA controller busy while we go
+ * ahead and free the descriptors below.
+ */
+ xgene_chan_xfer_ld_pending(chan);
+}
+
+static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan)
+{
+ struct xgene_dma_chan *chan = to_dma_chan(dchan);
+
+ /* Has this channel already been allocated? */
+ if (chan->desc_pool)
+ return 1;
+
+ chan->desc_pool = dma_pool_create(chan->name, chan->dev,
+ sizeof(struct xgene_dma_desc_sw),
+ 0, 0);
+ if (!chan->desc_pool) {
+ chan_err(chan, "Failed to allocate descriptor pool\n");
+ return -ENOMEM;
+ }
+
+ chan_dbg(chan, "Allocate descripto pool\n");
+
+ return 1;
+}
+
+/**
+ * xgene_dma_free_desc_list - Free all descriptors in a queue
+ * @chan: DMA channel
+ * @list: the list to free
+ *
+ * LOCKING: must hold chan->desc_lock
+ */
+static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan,
+ struct list_head *list)
+{
+ struct xgene_dma_desc_sw *desc, *_desc;
+
+ list_for_each_entry_safe(desc, _desc, list, node)
+ xgene_dma_free_descriptor(chan, desc);
+}
+
+static void xgene_dma_free_desc_list_reverse(struct xgene_dma_chan *chan,
+ struct list_head *list)
+{
+ struct xgene_dma_desc_sw *desc, *_desc;
+
+ list_for_each_entry_safe_reverse(desc, _desc, list, node)
+ xgene_dma_free_descriptor(chan, desc);
+}
+
+static void xgene_dma_free_chan_resources(struct dma_chan *dchan)
+{
+ struct xgene_dma_chan *chan = to_dma_chan(dchan);
+
+ chan_dbg(chan, "Free all resources\n");
+
+ if (!chan->desc_pool)
+ return;
+
+ spin_lock_bh(&chan->lock);
+
+ /* Process all running descriptor */
+ xgene_dma_cleanup_descriptors(chan);
+
+ /* Clean all link descriptor queues */
+ xgene_dma_free_desc_list(chan, &chan->ld_pending);
+ xgene_dma_free_desc_list(chan, &chan->ld_running);
+ xgene_dma_free_desc_list(chan, &chan->ld_completed);
+
+ /* Delete this channel DMA pool */
+ dma_pool_destroy(chan->desc_pool);
+ chan->desc_pool = NULL;
+
+ spin_unlock_bh(&chan->lock);
+}
+
+static struct dma_async_tx_descriptor *xgene_dma_prep_memcpy(
+ struct dma_chan *dchan, dma_addr_t dst, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct xgene_dma_desc_sw *first = NULL, *new;
+ struct xgene_dma_chan *chan;
+ size_t copy;
+
+ if (unlikely(!dchan || (len == 0)))
+ return NULL;
+
+ chan = to_dma_chan(dchan);
+
+ do {
+ /* Allocate the link descriptor from DMA pool */
+ new = xgene_dma_alloc_descriptor(chan);
+ if (!new)
+ goto fail;
+
+ /* Create the largest transaction possible */
+ copy = min_t(size_t, len, DMA_MAX_64B_DESC_BYTE_CNT);
+
+ /* Prepare DMA descriptor */
+ xgene_dma_prep_cpy_desc(chan, new, dst, src, copy);
+
+ if (!first)
+ first = new;
+
+ new->tx.cookie = 0;
+ async_tx_ack(&new->tx);
+
+ /* Update metadata */
+ len -= copy;
+ dst += copy;
+ src += copy;
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->tx_list);
+ } while (len);
+
+ new->tx.flags = flags; /* client is in control of this ack */
+ new->tx.cookie = -EBUSY;
+ list_splice(&first->tx_list, &new->tx_list);
+
+ return &new->tx;
+
+fail:
+ if (!first)
+ return NULL;
+
+ xgene_dma_free_desc_list_reverse(chan, &first->tx_list);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *xgene_dma_prep_sg(
+ struct dma_chan *dchan, struct scatterlist *dst_sg,
+ unsigned int dst_nents, struct scatterlist *src_sg,
+ unsigned int src_nents, unsigned long flags)
+{
+ struct xgene_dma_desc_sw *first = NULL, *new = NULL;
+ struct xgene_dma_chan *chan;
+ size_t dst_avail, src_avail;
+ dma_addr_t dst, src;
+ size_t len;
+
+ if (unlikely(!dchan))
+ return NULL;
+
+ if (unlikely(dst_nents == 0 || src_nents == 0))
+ return NULL;
+
+ if (unlikely(!dst_sg || !src_sg))
+ return NULL;
+
+ chan = to_dma_chan(dchan);
+
+ /* Get prepared for the loop */
+ dst_avail = sg_dma_len(dst_sg);
+ src_avail = sg_dma_len(src_sg);
+ dst_nents--;
+ src_nents--;
+
+ /* Run until we are out of scatterlist entries */
+ while (true) {
+ /* Create the largest transaction possible */
+ len = min_t(size_t, src_avail, dst_avail);
+ len = min_t(size_t, len, DMA_MAX_64B_DESC_BYTE_CNT);
+ if (len == 0)
+ goto fetch;
+
+ dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail;
+ src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail;
+
+ /* Allocate the link descriptor from DMA pool */
+ new = xgene_dma_alloc_descriptor(chan);
+ if (!new)
+ goto fail;
+
+ /* Prepare DMA descriptor */
+ xgene_dma_prep_cpy_desc(chan, new, dst, src, len);
+
+ if (!first)
+ first = new;
+
+ new->tx.cookie = 0;
+ async_tx_ack(&new->tx);
+
+ /* update metadata */
+ dst_avail -= len;
+ src_avail -= len;
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->tx_list);
+
+fetch:
+ /* fetch the next dst scatterlist entry */
+ if (dst_avail == 0) {
+ /* no more entries: we're done */
+ if (dst_nents == 0)
+ break;
+
+ /* fetch the next entry: if there are no more: done */
+ dst_sg = sg_next(dst_sg);
+ if (!dst_sg)
+ break;
+
+ dst_nents--;
+ dst_avail = sg_dma_len(dst_sg);
+ }
+
+ /* fetch the next src scatterlist entry */
+ if (src_avail == 0) {
+ /* no more entries: we're done */
+ if (src_nents == 0)
+ break;
+
+ /* fetch the next entry: if there are no more: done */
+ src_sg = sg_next(src_sg);
+ if (!src_sg)
+ break;
+
+ src_nents--;
+ src_avail = sg_dma_len(src_sg);
+ }
+ }
+
+ if (!new)
+ return NULL;
+
+ new->tx.flags = flags; /* client is in control of this ack */
+ new->tx.cookie = -EBUSY;
+ list_splice(&first->tx_list, &new->tx_list);
+
+ return &new->tx;
+
+fail:
+ if (!first)
+ return NULL;
+
+ xgene_dma_free_desc_list_reverse(chan, &first->tx_list);
+ return NULL;
+}
+
+static void xgene_dma_issue_pending(struct dma_chan *dchan)
+{
+ struct xgene_dma_chan *chan = to_dma_chan(dchan);
+
+ spin_lock_bh(&chan->lock);
+ xgene_chan_xfer_ld_pending(chan);
+ spin_unlock_bh(&chan->lock);
+}
+
+static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct xgene_dma_chan *chan = to_dma_chan(dchan);
+ enum dma_status status;
+
+ status = dma_cookie_status(dchan, cookie, txstate);
+ if (status == DMA_COMPLETE)
+ return status;
+
+ /* Cleanup any running and executed descriptors */
+ spin_lock_bh(&chan->lock);
+ xgene_dma_cleanup_descriptors(chan);
+ spin_unlock_bh(&chan->lock);
+
+ return dma_cookie_status(dchan, cookie, txstate);
+}
+
+static void xgene_dma_tasklet_cb(unsigned long data)
+{
+ struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data;
+
+ spin_lock_bh(&chan->lock);
+
+ /* Run all cleanup for descriptors which have been completed */
+ xgene_dma_cleanup_descriptors(chan);
+
+ /* Re-enable DMA channel IRQ */
+ enable_irq(chan->rx_irq);
+
+ spin_unlock_bh(&chan->lock);
+}
+
+static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id)
+{
+ struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id;
+
+ BUG_ON(!chan);
+
+ /*
+ * Disable DMA channel IRQ until we process completed
+ * descriptors
+ */
+ disable_irq_nosync(chan->rx_irq);
+
+ /*
+ * Schedule the tasklet to handle all cleanup of the current
+ * transaction. It will start a new transaction if there is
+ * one pending.
+ */
+ tasklet_schedule(&chan->tasklet);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t xgene_dma_err_isr(int irq, void *id)
+{
+ struct xgene_dma *pdma = (struct xgene_dma *)id;
+ unsigned long int_mask;
+ u32 val, i;
+
+ val = ioread32(pdma->csr_dma + DMA_INT);
+
+ /* Clear DMA interrupts */
+ iowrite32(val, pdma->csr_dma + DMA_INT);
+
+ /* Print DMA error info */
+ int_mask = val >> DMA_INT_MASK_SHIFT;
+ for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err))
+ dev_err(pdma->dev,
+ "Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]);
+
+ return IRQ_HANDLED;
+}
+
+static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring)
+{
+ int i;
+
+ iowrite32(ring->num, ring->pdma->csr_ring + DMA_RING_STATE);
+
+ for (i = 0; i < DMA_RING_NUM_CONFIG; i++)
+ iowrite32(ring->state[i], ring->pdma->csr_ring +
+ DMA_RING_STATE_WR_BASE + (i * 4));
+}
+
+static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring)
+{
+ memset(ring->state, 0, sizeof(u32) * DMA_RING_NUM_CONFIG);
+ xgene_dma_wr_ring_state(ring);
+}
+
+static void xgene_dma_setup_ring(struct xgene_dma_ring *ring)
+{
+ void *ring_cfg = ring->state;
+ u64 addr = ring->desc_paddr;
+ void *desc;
+ u32 i, val;
+
+ ring->slots = ring->size / DMA_RING_WQ_DESC_SIZE;
+
+ /* Clear DMA ring state */
+ xgene_dma_clr_ring_state(ring);
+
+ /* Set DMA ring type */
+ DMA_RING_TYPE_SET(ring_cfg, DMA_RING_TYPE_REGULAR);
+
+ if (ring->owner == DMA_RING_OWNER_DMA) {
+ /* Set recombination buffer and timeout */
+ DMA_RING_RECOMBBUF_SET(ring_cfg);
+ DMA_RING_RECOMTIMEOUTL_SET(ring_cfg);
+ DMA_RING_RECOMTIMEOUTH_SET(ring_cfg);
+ }
+
+ /* Initialize DMA ring state */
+ DMA_RING_SELTHRSH_SET(ring_cfg);
+ DMA_RING_ACCEPTLERR_SET(ring_cfg);
+ DMA_RING_COHERENT_SET(ring_cfg);
+ DMA_RING_ADDRL_SET(ring_cfg, addr);
+ DMA_RING_ADDRH_SET(ring_cfg, addr);
+ DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize);
+
+ /* Write DMA ring configurations */
+ xgene_dma_wr_ring_state(ring);
+
+ /* Set DMA ring id */
+ iowrite32(DMA_RING_ID_SETUP(ring->id),
+ ring->pdma->csr_ring + DMA_RING_ID);
+
+ /* Set DMA ring buffer */
+ iowrite32(DMA_RING_ID_BUF_SETUP(ring->num),
+ ring->pdma->csr_ring + DMA_RING_ID_BUF);
+
+ if (ring->owner != DMA_RING_OWNER_CPU)
+ return;
+
+ /* Set empty signature to DMA Rx ring descriptors */
+ for (i = 0; i < ring->slots; i++) {
+ desc = &ring->desc_hw[i];
+ DMA_DESC_SET_EMPTY(desc);
+ }
+
+ /* Enable DMA Rx ring interrupt */
+ val = ioread32(ring->pdma->csr_ring + DMA_RING_NE_INT_MODE);
+ DMA_RING_NE_INT_MODE_SET(val, ring->buf_num);
+ iowrite32(val, ring->pdma->csr_ring + DMA_RING_NE_INT_MODE);
+}
+
+static void xgene_dma_clear_ring(struct xgene_dma_ring *ring)
+{
+ u32 ring_id, val;
+
+ if (ring->owner == DMA_RING_OWNER_CPU) {
+ /* Disable DMA Rx ring interrupt */
+ val = ioread32(ring->pdma->csr_ring + DMA_RING_NE_INT_MODE);
+ DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num);
+ iowrite32(val, ring->pdma->csr_ring + DMA_RING_NE_INT_MODE);
+ }
+
+ /* Clear DMA ring state */
+ ring_id = DMA_RING_ID_SETUP(ring->id);
+ iowrite32(ring_id, ring->pdma->csr_ring + DMA_RING_ID);
+
+ iowrite32(0, ring->pdma->csr_ring + DMA_RING_ID_BUF);
+ xgene_dma_clr_ring_state(ring);
+}
+
+static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring)
+{
+ ring->cmd_base = ring->pdma->csr_ring_cmd +
+ DMA_RING_CMD_BASE_OFFSET((ring->num - DMA_RING_NUM));
+ ring->cmd = ring->cmd_base + DMA_RING_CMD_OFFSET;
+}
+
+static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan,
+ enum xgene_dma_ring_cfgsize cfgsize)
+{
+ int size;
+
+ switch (cfgsize) {
+ case DMA_RING_CFG_SIZE_512B:
+ size = 0x200;
+ break;
+ case DMA_RING_CFG_SIZE_2KB:
+ size = 0x800;
+ break;
+ case DMA_RING_CFG_SIZE_16KB:
+ size = 0x4000;
+ break;
+ case DMA_RING_CFG_SIZE_64KB:
+ size = 0x10000;
+ break;
+ case DMA_RING_CFG_SIZE_512KB:
+ size = 0x80000;
+ break;
+ default:
+ chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize);
+ return -EINVAL;
+ }
+
+ return size;
+}
+
+static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring)
+{
+ /* Clear DMA ring configurations */
+ xgene_dma_clear_ring(ring);
+
+ /* De-allocate DMA ring descriptor */
+ if (ring->desc_vaddr) {
+ dma_free_coherent(ring->pdma->dev, ring->size,
+ ring->desc_vaddr, ring->desc_paddr);
+ ring->desc_vaddr = NULL;
+ }
+}
+
+static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan)
+{
+ xgene_dma_delete_ring_one(&chan->rx_ring);
+ xgene_dma_delete_ring_one(&chan->tx_ring);
+}
+
+static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan,
+ struct xgene_dma_ring *ring,
+ enum xgene_dma_ring_cfgsize cfgsize)
+{
+ /* Setup DMA ring descriptor variables */
+ ring->pdma = chan->pdma;
+ ring->cfgsize = cfgsize;
+ ring->num = chan->pdma->ring_num++;
+ ring->id = DMA_RING_ID_GET(ring->owner, ring->buf_num);
+
+ ring->size = xgene_dma_get_ring_size(chan, cfgsize);
+ if (ring->size <= 0)
+ return ring->size;
+
+ /* Allocate memory for DMA ring descriptor */
+ ring->desc_vaddr = dma_zalloc_coherent(chan->dev, ring->size,
+ &ring->desc_paddr, GFP_KERNEL);
+ if (!ring->desc_vaddr) {
+ chan_err(chan, "Failed to allocate ring desc\n");
+ return -ENOMEM;
+ }
+
+ /* Configure and enable DMA ring */
+ xgene_dma_set_ring_cmd(ring);
+ xgene_dma_setup_ring(ring);
+
+ return 0;
+}
+
+static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan)
+{
+ struct xgene_dma_ring *rx_ring = &chan->rx_ring;
+ struct xgene_dma_ring *tx_ring = &chan->tx_ring;
+ int ret;
+
+ /* Create DMA Rx ring descriptor */
+ rx_ring->owner = DMA_RING_OWNER_CPU;
+ rx_ring->buf_num = DMA_CPU_BUFNUM + chan->id;
+
+ ret = xgene_dma_create_ring_one(chan, rx_ring, DMA_RING_CFG_SIZE_64KB);
+ if (ret)
+ return ret;
+
+ chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n",
+ rx_ring->id, rx_ring->num, rx_ring->desc_vaddr);
+
+ /* Create DMA Tx ring descriptor */
+ tx_ring->owner = DMA_RING_OWNER_DMA;
+ tx_ring->buf_num = DMA_BUFNUM + chan->id;
+
+ ret = xgene_dma_create_ring_one(chan, tx_ring, DMA_RING_CFG_SIZE_64KB);
+ if (ret) {
+ xgene_dma_delete_ring_one(rx_ring);
+ return ret;
+ }
+
+ tx_ring->dst_ring_num = DMA_RING_DST_ID(rx_ring->num);
+
+ chan_dbg(chan,
+ "Tx ring id 0x%X num %d desc 0x%p\n",
+ tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
+
+ return ret;
+}
+
+static int xgene_dma_init_rings(struct xgene_dma *pdma)
+{
+ int ret, i, j;
+
+ for (i = 0; i < DMA_MAX_CHANNEL; i++) {
+ ret = xgene_dma_create_chan_rings(&pdma->chan[i]);
+ if (ret) {
+ for (j = 0; j < i; j++)
+ xgene_dma_delete_chan_rings(&pdma->chan[j]);
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+static void xgene_dma_enable(struct xgene_dma *pdma)
+{
+ u32 val;
+
+ /* Configure and enable DMA engine */
+ val = ioread32(pdma->csr_dma + DMA_GCR);
+ DMA_CH_SETUP(val);
+ DMA_ENABLE(val);
+ iowrite32(val, pdma->csr_dma + DMA_GCR);
+}
+
+static void xgene_dma_disable(struct xgene_dma *pdma)
+{
+ u32 val;
+
+ val = ioread32(pdma->csr_dma + DMA_GCR);
+ DMA_DISABLE(val);
+ iowrite32(val, pdma->csr_dma + DMA_GCR);
+}
+
+static void xgene_dma_mask_interrupts(struct xgene_dma *pdma)
+{
+ /*
+ * Mask DMA ring overflow, underflow and
+ * AXI write/read error interrupts
+ */
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT0_MASK);
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT1_MASK);
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT2_MASK);
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT3_MASK);
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT4_MASK);
+
+ /* Mask DMA error interrupts */
+ iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_INT_MASK);
+}
+
+static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma)
+{
+ /*
+ * Unmask DMA ring overflow, underflow and
+ * AXI write/read error interrupts
+ */
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT0_MASK);
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT1_MASK);
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT2_MASK);
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT3_MASK);
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT4_MASK);
+
+ /* Unmask DMA error interrupts */
+ iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_INT_MASK);
+}
+
+static void xgene_dma_init_hw(struct xgene_dma *pdma)
+{
+ u32 val;
+
+ /* Associate DMA ring to corresponding ring HW */
+ iowrite32(DMA_ASSOC_RING_MNGR1,
+ pdma->csr_dma + DMA_CFG_RING_WQ_ASSOC);
+
+ xgene_dma_enable(pdma);
+ xgene_dma_unmask_interrupts(pdma);
+
+ /* Get DMA id and version info */
+ val = ioread32(pdma->csr_dma + DMA_IPBRR);
+
+ /* DMA device info */
+ dev_info(pdma->dev,
+ "X-Gene DMA v%d.%02d.%02d driver registered %d channels",
+ DMA_REV_NO_RD(val), DMA_BUS_ID_RD(val),
+ DMA_DEV_ID_RD(val), DMA_MAX_CHANNEL);
+}
+
+int xgene_dma_init_ring_mngr(struct xgene_dma *pdma)
+{
+ if (ioread32(pdma->csr_ring + DMA_RING_CLKEN) &&
+ (!ioread32(pdma->csr_ring + DMA_RING_SRST)))
+ return 0;
+
+ iowrite32(0x3, pdma->csr_ring + DMA_RING_CLKEN);
+ iowrite32(0x0, pdma->csr_ring + DMA_RING_SRST);
+
+ /* Bring up memory */
+ iowrite32(0x0, pdma->csr_ring + DMA_RING_MEM_RAM_SHUTDOWN);
+
+ /* Force a barrier */
+ ioread32(pdma->csr_ring + DMA_RING_MEM_RAM_SHUTDOWN);
+
+ /* reset may take up to 1ms */
+ usleep_range(1000, 1100);
+
+ if (ioread32(pdma->csr_ring + DMA_RING_BLK_MEM_RDY)
+ != DMA_RING_BLK_MEM_RDY_VAL) {
+ dev_err(pdma->dev,
+ "Failed to release ring mngr memory from shutdown\n");
+ return -ENODEV;
+ }
+
+ /* program threshold set 1 and all hysteresis */
+ iowrite32(DMA_RING_THRESLD0_SET1_VAL,
+ pdma->csr_ring + DMA_RING_THRESLD0_SET1);
+ iowrite32(DMA_RING_THRESLD1_SET1_VAL,
+ pdma->csr_ring + DMA_RING_THRESLD1_SET1);
+ iowrite32(DMA_RING_HYSTERESIS_VAL,
+ pdma->csr_ring + DMA_RING_HYSTERESIS);
+
+ /* Enable QPcore and assign error queue */
+ iowrite32(DMA_RING_ENABLE, pdma->csr_ring + DMA_RING_CONFIG);
+
+ return 0;
+}
+
+static int xgene_dma_init_mem(struct xgene_dma *pdma)
+{
+ int ret;
+
+ ret = xgene_dma_init_ring_mngr(pdma);
+ if (ret)
+ return ret;
+
+ /* Bring up memory */
+ iowrite32(0x0, pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN);
+
+ /* Force a barrier */
+ ioread32(pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN);
+
+ /* reset may take up to 1ms */
+ usleep_range(1000, 1100);
+
+ if (ioread32(pdma->csr_dma + DMA_BLK_MEM_RDY)
+ != DMA_BLK_MEM_RDY_VAL) {
+ dev_err(pdma->dev,
+ "Failed to release DMA memory from shutdown\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int xgene_dma_request_irqs(struct xgene_dma *pdma)
+{
+ struct xgene_dma_chan *chan;
+ int ret, i, j;
+
+ /* Register DMA error irq */
+ ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr,
+ 0, "dma_error", pdma);
+ if (ret) {
+ dev_err(pdma->dev,
+ "Failed to register error IRQ %d\n", pdma->err_irq);
+ return ret;
+ }
+
+ /* Register DMA channel rx irq */
+ for (i = 0; i < DMA_MAX_CHANNEL; i++) {
+ chan = &pdma->chan[i];
+ ret = devm_request_irq(chan->dev, chan->rx_irq,
+ xgene_dma_chan_ring_isr,
+ 0, chan->name, chan);
+ if (ret) {
+ chan_err(chan, "Failed to register Rx IRQ %d\n",
+ chan->rx_irq);
+ devm_free_irq(pdma->dev, pdma->err_irq, pdma);
+
+ for (j = 0; j < i; j++) {
+ chan = &pdma->chan[i];
+ devm_free_irq(chan->dev, chan->rx_irq, chan);
+ }
+
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void xgene_dma_free_irqs(struct xgene_dma *pdma)
+{
+ struct xgene_dma_chan *chan;
+ int i;
+
+ /* Free DMA device error irq */
+ devm_free_irq(pdma->dev, pdma->err_irq, pdma);
+
+ for (i = 0; i < DMA_MAX_CHANNEL; i++) {
+ chan = &pdma->chan[i];
+ devm_free_irq(chan->dev, chan->rx_irq, chan);
+ }
+}
+
+static void xgene_dma_set_caps(struct xgene_dma_chan *chan,
+ struct dma_device *dma_dev)
+{
+ /* Initialize DMA device capability mask */
+ dma_cap_zero(dma_dev->cap_mask);
+
+ /* Set DMA device capability */
+ dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
+ dma_cap_set(DMA_SG, dma_dev->cap_mask);
+
+ /* Set base and prep routines */
+ dma_dev->dev = chan->dev;
+ dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources;
+ dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources;
+ dma_dev->device_issue_pending = xgene_dma_issue_pending;
+ dma_dev->device_tx_status = xgene_dma_tx_status;
+ dma_dev->device_prep_dma_memcpy = xgene_dma_prep_memcpy;
+ dma_dev->device_prep_dma_sg = xgene_dma_prep_sg;
+}
+
+static int xgene_dma_async_register(struct xgene_dma *pdma, int id)
+{
+ struct xgene_dma_chan *chan = &pdma->chan[id];
+ struct dma_device *dma_dev = &pdma->dma_dev[id];
+ int ret;
+
+ chan->dma_chan.device = dma_dev;
+
+ spin_lock_init(&chan->lock);
+ INIT_LIST_HEAD(&chan->ld_pending);
+ INIT_LIST_HEAD(&chan->ld_running);
+ INIT_LIST_HEAD(&chan->ld_completed);
+ tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb,
+ (unsigned long)chan);
+
+ chan->pending = 0;
+ chan->desc_pool = NULL;
+ dma_cookie_init(&chan->dma_chan);
+
+ /* Setup dma device capabilities and prep routines */
+ xgene_dma_set_caps(chan, dma_dev);
+
+ /* Initialize DMA device list head */
+ INIT_LIST_HEAD(&dma_dev->channels);
+ list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels);
+
+ /* Register with Linux async DMA framework*/
+ ret = dma_async_device_register(dma_dev);
+ if (ret) {
+ chan_err(chan, "Failed to register async device %d", ret);
+ tasklet_kill(&chan->tasklet);
+
+ return ret;
+ }
+
+ /* DMA capability info */
+ dev_info(pdma->dev,
+ "%s: CAPABILITY ( %s%s)\n", dma_chan_name(&chan->dma_chan),
+ dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "MEMCPY " : "",
+ dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "SGCPY " : "");
+
+ return 0;
+}
+
+static int xgene_dma_init_async(struct xgene_dma *pdma)
+{
+ int ret, i, j;
+
+ for (i = 0; i < DMA_MAX_CHANNEL ; i++) {
+ ret = xgene_dma_async_register(pdma, i);
+ if (ret) {
+ for (j = 0; j < i; j++) {
+ dma_async_device_unregister(&pdma->dma_dev[j]);
+ tasklet_kill(&pdma->chan[j].tasklet);
+ }
+
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+static void xgene_dma_async_unregister(struct xgene_dma *pdma)
+{
+ int i;
+
+ for (i = 0; i < DMA_MAX_CHANNEL; i++)
+ dma_async_device_unregister(&pdma->dma_dev[i]);
+}
+
+static void xgene_dma_init_channels(struct xgene_dma *pdma)
+{
+ struct xgene_dma_chan *chan;
+ int i;
+
+ pdma->ring_num = DMA_RING_NUM;
+
+ for (i = 0; i < DMA_MAX_CHANNEL; i++) {
+ chan = &pdma->chan[i];
+ chan->dev = pdma->dev;
+ chan->pdma = pdma;
+ chan->id = i;
+ sprintf(chan->name, "chan%d", chan->id);
+ }
+}
+
+static int xgene_dma_get_resources(struct platform_device *pdev,
+ struct xgene_dma *pdma)
+{
+ struct resource *res;
+ int irq, i;
+
+ /* Get DMA csr region */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma_csr");
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get csr region\n");
+ return -ENXIO;
+ }
+
+ pdma->csr_dma = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (IS_ERR(pdma->csr_dma)) {
+ dev_err(&pdev->dev, "Failed to ioremap csr region");
+ return PTR_ERR(pdma->csr_dma);
+ }
+
+ /* Get DMA ring csr region */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ring_csr");
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get ring csr region\n");
+ return -ENXIO;
+ }
+
+ pdma->csr_ring = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (IS_ERR(pdma->csr_ring)) {
+ dev_err(&pdev->dev, "Failed to ioremap ring csr region");
+ return PTR_ERR(pdma->csr_ring);
+ }
+
+ /* Get DMA ring cmd csr region */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "ring_cmd_csr");
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get ring cmd csr region\n");
+ return -ENXIO;
+ }
+
+ pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (IS_ERR(pdma->csr_ring_cmd)) {
+ dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region");
+ return PTR_ERR(pdma->csr_ring_cmd);
+ }
+
+ /* Get DMA error interrupt */
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "Failed to get Error IRQ\n");
+ return -ENXIO;
+ }
+
+ pdma->err_irq = irq;
+
+ /* Get DMA Rx ring descriptor interrupts for all DMA channels */
+ for (i = 1; i <= DMA_MAX_CHANNEL; i++) {
+ irq = platform_get_irq(pdev, i);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "Failed to get Rx IRQ\n");
+ return -ENXIO;
+ }
+
+ pdma->chan[i - 1].rx_irq = irq;
+ }
+
+ return 0;
+}
+
+static int xgene_dma_probe(struct platform_device *pdev)
+{
+ struct xgene_dma *pdma;
+ int ret, i;
+
+ pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL);
+ if (!pdma)
+ return -ENOMEM;
+
+ pdma->dev = &pdev->dev;
+ platform_set_drvdata(pdev, pdma);
+
+ ret = xgene_dma_get_resources(pdev, pdma);
+ if (ret)
+ return ret;
+
+ pdma->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(pdma->clk)) {
+ dev_err(&pdev->dev, "Failed to get clk\n");
+ return PTR_ERR(pdma->clk);
+ }
+
+ /* Enable clk before accessing registers */
+ ret = clk_prepare_enable(pdma->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to enable clk %d\n", ret);
+ return ret;
+ }
+
+ /* Remove DMA RAM out of shutdown */
+ ret = xgene_dma_init_mem(pdma);
+ if (ret)
+ goto err_clk_enable;
+
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42));
+ if (ret) {
+ dev_err(&pdev->dev, "No usable DMA configuration\n");
+ goto err_dma_mask;
+ }
+
+ /* Initialize DMA channels software state */
+ xgene_dma_init_channels(pdma);
+
+ /* Configue DMA rings */
+ ret = xgene_dma_init_rings(pdma);
+ if (ret)
+ goto err_clk_enable;
+
+ ret = xgene_dma_request_irqs(pdma);
+ if (ret)
+ goto err_request_irq;
+
+ /* Configure and enable DMA engine */
+ xgene_dma_init_hw(pdma);
+
+ /* Register DMA device with linux async framework */
+ ret = xgene_dma_init_async(pdma);
+ if (ret)
+ goto err_async_init;
+
+ return 0;
+
+err_async_init:
+ xgene_dma_free_irqs(pdma);
+
+err_request_irq:
+ for (i = 0; i < DMA_MAX_CHANNEL; i++)
+ xgene_dma_delete_chan_rings(&pdma->chan[i]);
+
+err_dma_mask:
+err_clk_enable:
+ clk_disable_unprepare(pdma->clk);
+
+ return ret;
+}
+
+static int xgene_dma_remove(struct platform_device *pdev)
+{
+ struct xgene_dma *pdma = platform_get_drvdata(pdev);
+ struct xgene_dma_chan *chan;
+ int i;
+
+ xgene_dma_async_unregister(pdma);
+
+ /* Mask interrupts and disable DMA engine */
+ xgene_dma_mask_interrupts(pdma);
+ xgene_dma_disable(pdma);
+ xgene_dma_free_irqs(pdma);
+
+ for (i = 0; i < DMA_MAX_CHANNEL; i++) {
+ chan = &pdma->chan[i];
+ tasklet_kill(&chan->tasklet);
+ xgene_dma_delete_chan_rings(chan);
+ }
+
+ clk_disable_unprepare(pdma->clk);
+
+ return 0;
+}
+
+static const struct of_device_id xgene_dma_of_match_ptr[] = {
+ {.compatible = "apm,xgene-dma",},
+ {},
+};
+MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr);
+
+static struct platform_driver xgene_dma_driver = {
+ .probe = xgene_dma_probe,
+ .remove = xgene_dma_remove,
+ .driver = {
+ .name = "X-Gene-DMA",
+ .owner = THIS_MODULE,
+ .of_match_table = xgene_dma_of_match_ptr,
+ },
+};
+
+module_platform_driver(xgene_dma_driver);
+
+MODULE_DESCRIPTION("APM X-Gene SoC DMA driver");
+MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@xxxxxxx>");
+MODULE_AUTHOR("Loc Ho <lho@xxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0");
--
1.8.2.1
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