[PATCH v9 1/3] dmaengine: ptdma: Initial driver for the AMD PTDMA
From: Sanjay R Mehta
Date: Wed Jun 02 2021 - 13:22:59 EST
From: Sanjay R Mehta <sanju.mehta@xxxxxxx>
Add support for AMD PTDMA controller. It performs high-bandwidth
memory to memory and IO copy operation. Device commands are managed
via a circular queue of 'descriptors', each of which specifies source
and destination addresses for copying a single buffer of data.
Signed-off-by: Sanjay R Mehta <sanju.mehta@xxxxxxx>
---
MAINTAINERS | 6 +
drivers/dma/Kconfig | 2 +
drivers/dma/Makefile | 1 +
drivers/dma/ptdma/Kconfig | 11 ++
drivers/dma/ptdma/Makefile | 10 ++
drivers/dma/ptdma/ptdma-dev.c | 290 +++++++++++++++++++++++++++++++++++++++
drivers/dma/ptdma/ptdma-pci.c | 251 ++++++++++++++++++++++++++++++++++
drivers/dma/ptdma/ptdma.h | 305 ++++++++++++++++++++++++++++++++++++++++++
8 files changed, 876 insertions(+)
create mode 100644 drivers/dma/ptdma/Kconfig
create mode 100644 drivers/dma/ptdma/Makefile
create mode 100644 drivers/dma/ptdma/ptdma-dev.c
create mode 100644 drivers/dma/ptdma/ptdma-pci.c
create mode 100644 drivers/dma/ptdma/ptdma.h
diff --git a/MAINTAINERS b/MAINTAINERS
index bd7aff0c..2c897fa 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -957,6 +957,12 @@ S: Supported
T: git git://people.freedesktop.org/~agd5f/linux
F: drivers/gpu/drm/amd/pm/powerplay/
++AMD PTDMA DRIVER
++M: Sanjay R Mehta <sanju.mehta@xxxxxxx>
++L: dmaengine@xxxxxxxxxxxxxxx
++S: Maintained
++F: drivers/dma/ptdma/
+
AMD SEATTLE DEVICE TREE SUPPORT
M: Brijesh Singh <brijeshkumar.singh@xxxxxxx>
M: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 6ab9d9a..7900f1a 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -714,6 +714,8 @@ source "drivers/dma/bestcomm/Kconfig"
source "drivers/dma/mediatek/Kconfig"
+source "drivers/dma/ptdma/Kconfig"
+
source "drivers/dma/qcom/Kconfig"
source "drivers/dma/dw/Kconfig"
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index aa69094..bf9ffc2 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_DMATEST) += dmatest.o
obj-$(CONFIG_ALTERA_MSGDMA) += altera-msgdma.o
obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o
obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/
+obj-$(CONFIG_AMD_PTDMA) += ptdma/
obj-$(CONFIG_AT_HDMAC) += at_hdmac.o
obj-$(CONFIG_AT_XDMAC) += at_xdmac.o
obj-$(CONFIG_AXI_DMAC) += dma-axi-dmac.o
diff --git a/drivers/dma/ptdma/Kconfig b/drivers/dma/ptdma/Kconfig
new file mode 100644
index 0000000..e6b8ca1
--- /dev/null
+++ b/drivers/dma/ptdma/Kconfig
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config AMD_PTDMA
+ tristate "AMD PassThru DMA Engine"
+ depends on X86_64 && PCI
+ help
+ Enable support for the AMD PTDMA controller. This controller
+ provides DMA capabilities to perform high bandwidth memory to
+ memory and IO copy operations. It performs DMA transfer through
+ queue-based descriptor management. This DMA controller is intended
+ to be used with AMD Non-Transparent Bridge devices and not for
+ general purpose peripheral DMA.
diff --git a/drivers/dma/ptdma/Makefile b/drivers/dma/ptdma/Makefile
new file mode 100644
index 0000000..320fa82
--- /dev/null
+++ b/drivers/dma/ptdma/Makefile
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# AMD Passthru DMA driver
+#
+
+obj-$(CONFIG_AMD_PTDMA) += ptdma.o
+
+ptdma-objs := ptdma-dev.o
+
+ptdma-$(CONFIG_PCI) += ptdma-pci.o
diff --git a/drivers/dma/ptdma/ptdma-dev.c b/drivers/dma/ptdma/ptdma-dev.c
new file mode 100644
index 0000000..4617550
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma-dev.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.mehta@xxxxxxx>
+ * Author: Gary R Hook <gary.hook@xxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/dma-mapping.h>
+#include <linux/debugfs.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "ptdma.h"
+
+/* Human-readable error strings */
+static char *pt_error_codes[] = {
+ "",
+ "ERR 01: ILLEGAL_ENGINE",
+ "ERR 03: ILLEGAL_FUNCTION_TYPE",
+ "ERR 04: ILLEGAL_FUNCTION_MODE",
+ "ERR 06: ILLEGAL_FUNCTION_SIZE",
+ "ERR 08: ILLEGAL_FUNCTION_RSVD",
+ "ERR 09: ILLEGAL_BUFFER_LENGTH",
+ "ERR 10: VLSB_FAULT",
+ "ERR 11: ILLEGAL_MEM_ADDR",
+ "ERR 12: ILLEGAL_MEM_SEL",
+ "ERR 13: ILLEGAL_CONTEXT_ID",
+ "ERR 15: 0xF Reserved",
+ "ERR 18: CMD_TIMEOUT",
+ "ERR 19: IDMA0_AXI_SLVERR",
+ "ERR 20: IDMA0_AXI_DECERR",
+ "ERR 21: 0x15 Reserved",
+ "ERR 22: IDMA1_AXI_SLAVE_FAULT",
+ "ERR 23: IDMA1_AIXI_DECERR",
+ "ERR 24: 0x18 Reserved",
+ "ERR 27: 0x1B Reserved",
+ "ERR 38: ODMA0_AXI_SLVERR",
+ "ERR 39: ODMA0_AXI_DECERR",
+ "ERR 40: 0x28 Reserved",
+ "ERR 41: ODMA1_AXI_SLVERR",
+ "ERR 42: ODMA1_AXI_DECERR",
+ "ERR 43: LSB_PARITY_ERR",
+};
+
+static void pt_log_error(struct pt_device *d, int e)
+{
+ dev_err(d->dev, "PTDMA error: %s (0x%x)\n", pt_error_codes[e], e);
+}
+
+void pt_start_queue(struct pt_cmd_queue *cmd_q)
+{
+ /* Turn on the run bit */
+ iowrite32(cmd_q->qcontrol | CMD_Q_RUN, cmd_q->reg_control);
+}
+
+void pt_stop_queue(struct pt_cmd_queue *cmd_q)
+{
+ /* Turn off the run bit */
+ iowrite32(cmd_q->qcontrol & ~CMD_Q_RUN, cmd_q->reg_control);
+}
+
+static int pt_core_execute_cmd(struct ptdma_desc *desc, struct pt_cmd_queue *cmd_q)
+{
+ bool soc = FIELD_GET(DWORD0_SOC, desc->dw0);
+ u8 *q_desc = (u8 *)&cmd_q->qbase[cmd_q->qidx];
+ u8 *dp = (u8 *)desc;
+ u32 tail;
+
+ if (soc) {
+ desc->dw0 |= FIELD_PREP(DWORD0_IOC, desc->dw0);
+ desc->dw0 &= ~DWORD0_SOC;
+ }
+ mutex_lock(&cmd_q->q_mutex);
+
+ /* Copy 32-byte command descriptor to hw queue. */
+ memcpy(q_desc, dp, 32);
+ cmd_q->qidx = (cmd_q->qidx + 1) % CMD_Q_LEN;
+
+ /* The data used by this command must be flushed to memory */
+ wmb();
+
+ /* Write the new tail address back to the queue register */
+ tail = lower_32_bits(cmd_q->qdma_tail + cmd_q->qidx * Q_DESC_SIZE);
+ iowrite32(tail, cmd_q->reg_tail_lo);
+
+ /* Turn the queue back on using our cached control register */
+ pt_start_queue(cmd_q);
+ mutex_unlock(&cmd_q->q_mutex);
+
+ return 0;
+}
+
+int pt_core_perform_passthru(struct pt_cmd_queue *cmd_q,
+ struct pt_passthru_engine *pt_engine)
+{
+ struct ptdma_desc desc;
+
+ cmd_q->cmd_error = 0;
+ memset(&desc, 0, sizeof(desc));
+ desc.dw0 = CMD_DESC_DW0_VAL;
+ desc.length = pt_engine->src_len;
+ desc.src_lo = lower_32_bits(pt_engine->src_dma);
+ desc.dw3.src_hi = upper_32_bits(pt_engine->src_dma);
+ desc.dst_lo = lower_32_bits(pt_engine->dst_dma);
+ desc.dw5.dst_hi = upper_32_bits(pt_engine->dst_dma);
+
+ return pt_core_execute_cmd(&desc, cmd_q);
+}
+
+static inline void pt_core_disable_queue_interrupts(struct pt_device *pt)
+{
+ iowrite32(0, pt->cmd_q.reg_int_enable);
+}
+
+static inline void pt_core_enable_queue_interrupts(struct pt_device *pt)
+{
+ iowrite32(SUPPORTED_INTERRUPTS, pt->cmd_q.reg_int_enable);
+}
+
+static irqreturn_t pt_core_irq_handler(int irq, void *data)
+{
+ struct pt_device *pt = data;
+ struct pt_cmd_queue *cmd_q = &pt->cmd_q;
+ u32 status;
+
+ pt_core_disable_queue_interrupts(pt);
+
+ status = ioread32(cmd_q->reg_interrupt_status);
+ if (status) {
+ cmd_q->int_status = status;
+ cmd_q->q_status = ioread32(cmd_q->reg_status);
+ cmd_q->q_int_status = ioread32(cmd_q->reg_int_status);
+
+ /* On error, only save the first error value */
+ if ((status & INT_ERROR) && !cmd_q->cmd_error)
+ cmd_q->cmd_error = CMD_Q_ERROR(cmd_q->q_status);
+
+ /* Acknowledge the interrupt */
+ iowrite32(status, cmd_q->reg_interrupt_status);
+ }
+
+ pt_core_enable_queue_interrupts(pt);
+
+ return IRQ_HANDLED;
+}
+
+static void pt_init_cmdq_regs(struct pt_cmd_queue *cmd_q)
+{
+ void __iomem *io_regs = cmd_q->reg_control;
+
+ cmd_q->reg_tail_lo = io_regs + CMD_Q_TAIL_LO_BASE;
+ cmd_q->reg_head_lo = io_regs + CMD_Q_HEAD_LO_BASE;
+ cmd_q->reg_status = io_regs + CMD_Q_STATUS_BASE;
+ cmd_q->reg_int_enable = io_regs + CMD_Q_INT_ENABLE_BASE;
+ cmd_q->reg_int_status = io_regs + CMD_Q_INT_STATUS_BASE;
+ cmd_q->reg_dma_status = io_regs + CMD_Q_DMA_STATUS_BASE;
+ cmd_q->reg_dma_read_status = io_regs + CMD_Q_DMA_READ_STATUS_BASE;
+ cmd_q->reg_dma_write_status = io_regs + CMD_Q_DMA_WRITE_STATUS_BASE;
+ cmd_q->reg_interrupt_status = io_regs + CMD_Q_INTERRUPT_STATUS_BASE;
+}
+
+int pt_core_init(struct pt_device *pt)
+{
+ char dma_pool_name[MAX_DMAPOOL_NAME_LEN];
+ struct pt_cmd_queue *cmd_q = &pt->cmd_q;
+ u32 dma_addr_lo, dma_addr_hi;
+ struct device *dev = pt->dev;
+ struct dma_pool *dma_pool;
+ int ret;
+
+ /* Allocate a dma pool for the queue */
+ snprintf(dma_pool_name, sizeof(dma_pool_name), "%s_q", pt->name);
+
+ dma_pool = dma_pool_create(dma_pool_name, dev,
+ PT_DMAPOOL_MAX_SIZE,
+ PT_DMAPOOL_ALIGN, 0);
+ if (!dma_pool) {
+ dev_err(dev, "unable to allocate dma pool\n");
+ return -ENOMEM;
+ }
+
+ /* ptdma core initialisation */
+ iowrite32(CMD_CONFIG_VHB_EN, pt->io_regs + CMD_CONFIG_OFFSET);
+ iowrite32(CMD_QUEUE_PRIO, pt->io_regs + CMD_QUEUE_PRIO_OFFSET);
+ iowrite32(CMD_TIMEOUT_DISABLE, pt->io_regs + CMD_TIMEOUT_OFFSET);
+ iowrite32(CMD_CLK_GATE_CONFIG, pt->io_regs + CMD_CLK_GATE_CTL_OFFSET);
+ iowrite32(CMD_CONFIG_REQID, pt->io_regs + CMD_REQID_CONFIG_OFFSET);
+
+ cmd_q->pt = pt;
+ cmd_q->dma_pool = dma_pool;
+ mutex_init(&cmd_q->q_mutex);
+
+ /* Page alignment satisfies our needs for N <= 128 */
+ cmd_q->qsize = Q_SIZE(Q_DESC_SIZE);
+ cmd_q->qbase = dma_alloc_coherent(dev, cmd_q->qsize,
+ &cmd_q->qbase_dma,
+ GFP_KERNEL);
+ if (!cmd_q->qbase) {
+ dev_err(dev, "unable to allocate command queue\n");
+ ret = -ENOMEM;
+ goto e_dma_alloc;
+ }
+
+ cmd_q->qidx = 0;
+
+ /* Preset some register values */
+ cmd_q->reg_control = pt->io_regs + CMD_Q_STATUS_INCR;
+ pt_init_cmdq_regs(cmd_q);
+
+ /* Turn off the queues and disable interrupts until ready */
+ pt_core_disable_queue_interrupts(pt);
+
+ cmd_q->qcontrol = 0; /* Start with nothing */
+ iowrite32(cmd_q->qcontrol, cmd_q->reg_control);
+
+ ioread32(cmd_q->reg_int_status);
+ ioread32(cmd_q->reg_status);
+
+ /* Clear the interrupt status */
+ iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_interrupt_status);
+
+ /* Request an irq */
+ ret = request_irq(pt->pt_irq, pt_core_irq_handler, 0, pt->name, pt);
+ if (ret)
+ goto e_pool;
+
+ /* Update the device registers with queue information. */
+ cmd_q->qcontrol &= ~CMD_Q_SIZE;
+ cmd_q->qcontrol |= FIELD_PREP(CMD_Q_SIZE, QUEUE_SIZE_VAL);
+
+ cmd_q->qdma_tail = cmd_q->qbase_dma;
+ dma_addr_lo = lower_32_bits(cmd_q->qdma_tail);
+ iowrite32((u32)dma_addr_lo, cmd_q->reg_tail_lo);
+ iowrite32((u32)dma_addr_lo, cmd_q->reg_head_lo);
+
+ dma_addr_hi = upper_32_bits(cmd_q->qdma_tail);
+ cmd_q->qcontrol |= (dma_addr_hi << 16);
+ iowrite32(cmd_q->qcontrol, cmd_q->reg_control);
+
+ pt_core_enable_queue_interrupts(pt);
+
+ return 0;
+
+e_dma_alloc:
+ dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase, cmd_q->qbase_dma);
+
+e_pool:
+ dev_err(dev, "unable to allocate an IRQ\n");
+ dma_pool_destroy(pt->cmd_q.dma_pool);
+
+ return ret;
+}
+
+void pt_core_destroy(struct pt_device *pt)
+{
+ struct device *dev = pt->dev;
+ struct pt_cmd_queue *cmd_q = &pt->cmd_q;
+ struct pt_cmd *cmd;
+
+ /* Disable and clear interrupts */
+ pt_core_disable_queue_interrupts(pt);
+
+ /* Turn off the run bit */
+ pt_stop_queue(cmd_q);
+
+ /* Clear the interrupt status */
+ iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_interrupt_status);
+ ioread32(cmd_q->reg_int_status);
+ ioread32(cmd_q->reg_status);
+
+ free_irq(pt->pt_irq, pt);
+
+ dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase,
+ cmd_q->qbase_dma);
+
+ /* Flush the cmd queue */
+ while (!list_empty(&pt->cmd)) {
+ /* Invoke the callback directly with an error code */
+ cmd = list_first_entry(&pt->cmd, struct pt_cmd, entry);
+ list_del(&cmd->entry);
+ cmd->pt_cmd_callback(cmd->data, -ENODEV);
+ }
+}
diff --git a/drivers/dma/ptdma/ptdma-pci.c b/drivers/dma/ptdma/ptdma-pci.c
new file mode 100644
index 0000000..0945c27
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma-pci.c
@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.mehta@xxxxxxx>
+ * Author: Tom Lendacky <thomas.lendacky@xxxxxxx>
+ * Author: Gary R Hook <gary.hook@xxxxxxx>
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/pci_ids.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+
+#include "ptdma.h"
+
+/* Ever-increasing value to produce unique unit numbers */
+static atomic_t pt_ordinal;
+
+struct pt_msix {
+ int msix_count;
+ struct msix_entry msix_entry;
+};
+
+/*
+ * pt_alloc_struct - allocate and initialize the pt_device struct
+ *
+ * @dev: device struct of the PTDMA
+ */
+static struct pt_device *pt_alloc_struct(struct device *dev)
+{
+ struct pt_device *pt;
+
+ pt = devm_kzalloc(dev, sizeof(*pt), GFP_KERNEL);
+
+ if (!pt)
+ return NULL;
+ pt->dev = dev;
+ pt->ord = atomic_inc_return(&pt_ordinal);
+
+ INIT_LIST_HEAD(&pt->cmd);
+
+ snprintf(pt->name, MAX_PT_NAME_LEN, "pt-%u", pt->ord);
+
+ return pt;
+}
+
+static int pt_get_msix_irqs(struct pt_device *pt)
+{
+ struct pt_msix *pt_msix = pt->pt_msix;
+ struct device *dev = pt->dev;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int ret;
+
+ pt_msix->msix_entry.entry = 0;
+
+ ret = pci_enable_msix_range(pdev, &pt_msix->msix_entry, 1, 1);
+ if (ret < 0)
+ return ret;
+
+ pt_msix->msix_count = ret;
+
+ pt->pt_irq = pt_msix->msix_entry.vector;
+
+ return 0;
+}
+
+static int pt_get_msi_irq(struct pt_device *pt)
+{
+ struct device *dev = pt->dev;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int ret;
+
+ ret = pci_enable_msi(pdev);
+ if (ret)
+ return ret;
+
+ pt->pt_irq = pdev->irq;
+
+ return 0;
+}
+
+static int pt_get_irqs(struct pt_device *pt)
+{
+ struct device *dev = pt->dev;
+ int ret;
+
+ ret = pt_get_msix_irqs(pt);
+ if (!ret)
+ return 0;
+
+ /* Couldn't get MSI-X vectors, try MSI */
+ dev_err(dev, "could not enable MSI-X (%d), trying MSI\n", ret);
+ ret = pt_get_msi_irq(pt);
+ if (!ret)
+ return 0;
+
+ /* Couldn't get MSI interrupt */
+ dev_err(dev, "could not enable MSI (%d)\n", ret);
+
+ return ret;
+}
+
+static void pt_free_irqs(struct pt_device *pt)
+{
+ struct pt_msix *pt_msix = pt->pt_msix;
+ struct device *dev = pt->dev;
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ if (pt_msix->msix_count)
+ pci_disable_msix(pdev);
+ else if (pt->pt_irq)
+ pci_disable_msi(pdev);
+
+ pt->pt_irq = 0;
+}
+
+static int pt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct pt_device *pt;
+ struct pt_msix *pt_msix;
+ struct device *dev = &pdev->dev;
+ void __iomem * const *iomap_table;
+ int bar_mask;
+ int ret = -ENOMEM;
+
+ pt = pt_alloc_struct(dev);
+ if (!pt)
+ goto e_err;
+
+ pt_msix = devm_kzalloc(dev, sizeof(*pt_msix), GFP_KERNEL);
+ if (!pt_msix)
+ goto e_err;
+
+ pt->pt_msix = pt_msix;
+ pt->dev_vdata = (struct pt_dev_vdata *)id->driver_data;
+ if (!pt->dev_vdata) {
+ ret = -ENODEV;
+ dev_err(dev, "missing driver data\n");
+ goto e_err;
+ }
+
+ ret = pcim_enable_device(pdev);
+ if (ret) {
+ dev_err(dev, "pcim_enable_device failed (%d)\n", ret);
+ goto e_err;
+ }
+
+ bar_mask = pci_select_bars(pdev, IORESOURCE_MEM);
+ ret = pcim_iomap_regions(pdev, bar_mask, "ptdma");
+ if (ret) {
+ dev_err(dev, "pcim_iomap_regions failed (%d)\n", ret);
+ goto e_err;
+ }
+
+ iomap_table = pcim_iomap_table(pdev);
+ if (!iomap_table) {
+ dev_err(dev, "pcim_iomap_table failed\n");
+ ret = -ENOMEM;
+ goto e_err;
+ }
+
+ pt->io_regs = iomap_table[pt->dev_vdata->bar];
+ if (!pt->io_regs) {
+ dev_err(dev, "ioremap failed\n");
+ ret = -ENOMEM;
+ goto e_err;
+ }
+
+ ret = pt_get_irqs(pt);
+ if (ret)
+ goto e_err;
+
+ pci_set_master(pdev);
+
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
+ if (ret) {
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+ if (ret) {
+ dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n",
+ ret);
+ goto e_err;
+ }
+ }
+
+ dev_set_drvdata(dev, pt);
+
+ if (pt->dev_vdata)
+ ret = pt_core_init(pt);
+
+ if (ret)
+ goto e_err;
+
+ dev_dbg(dev, "PTDMA enabled\n");
+
+ return 0;
+
+e_err:
+ dev_err(dev, "initialization failed\n");
+
+ return ret;
+}
+
+static void pt_pci_remove(struct pci_dev *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pt_device *pt = dev_get_drvdata(dev);
+
+ if (!pt)
+ return;
+
+ if (pt->dev_vdata)
+ pt_core_destroy(pt);
+
+ pt_free_irqs(pt);
+}
+
+static const struct pt_dev_vdata dev_vdata[] = {
+ {
+ .bar = 2,
+ },
+};
+
+static const struct pci_device_id pt_pci_table[] = {
+ { PCI_VDEVICE(AMD, 0x1498), (kernel_ulong_t)&dev_vdata[0] },
+ /* Last entry must be zero */
+ { 0, }
+};
+MODULE_DEVICE_TABLE(pci, pt_pci_table);
+
+static struct pci_driver pt_pci_driver = {
+ .name = "ptdma",
+ .id_table = pt_pci_table,
+ .probe = pt_pci_probe,
+ .remove = pt_pci_remove,
+};
+
+module_pci_driver(pt_pci_driver);
+
+MODULE_AUTHOR("Sanjay R Mehta <sanju.mehta@xxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("AMD PassThru DMA driver");
diff --git a/drivers/dma/ptdma/ptdma.h b/drivers/dma/ptdma/ptdma.h
new file mode 100644
index 0000000..a89a74ac
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma.h
@@ -0,0 +1,305 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.mehta@xxxxxxx>
+ * Author: Tom Lendacky <thomas.lendacky@xxxxxxx>
+ * Author: Gary R Hook <gary.hook@xxxxxxx>
+ */
+
+#ifndef __PT_DEV_H__
+#define __PT_DEV_H__
+
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/dmapool.h>
+
+#define MAX_PT_NAME_LEN 16
+#define MAX_DMAPOOL_NAME_LEN 32
+
+#define MAX_HW_QUEUES 1
+#define MAX_CMD_QLEN 100
+
+#define PT_ENGINE_PASSTHRU 5
+#define PT_OFFSET 0x0
+
+#define PT_VSIZE 16
+#define PT_VMASK ((unsigned int)((1 << PT_VSIZE) - 1))
+
+/* Register Mappings */
+#define IRQ_MASK_REG 0x040
+#define IRQ_STATUS_REG 0x200
+
+#define CMD_Q_ERROR(__qs) ((__qs) & 0x0000003f)
+
+#define CMD_QUEUE_PRIO_OFFSET 0x00
+#define CMD_REQID_CONFIG_OFFSET 0x04
+#define CMD_TIMEOUT_OFFSET 0x08
+#define CMD_PT_VERSION 0x10
+
+#define CMD_Q_CONTROL_BASE 0x0000
+#define CMD_Q_TAIL_LO_BASE 0x0004
+#define CMD_Q_HEAD_LO_BASE 0x0008
+#define CMD_Q_INT_ENABLE_BASE 0x000C
+#define CMD_Q_INTERRUPT_STATUS_BASE 0x0010
+
+#define CMD_Q_STATUS_BASE 0x0100
+#define CMD_Q_INT_STATUS_BASE 0x0104
+#define CMD_Q_DMA_STATUS_BASE 0x0108
+#define CMD_Q_DMA_READ_STATUS_BASE 0x010C
+#define CMD_Q_DMA_WRITE_STATUS_BASE 0x0110
+#define CMD_Q_ABORT_BASE 0x0114
+#define CMD_Q_AX_CACHE_BASE 0x0118
+
+#define CMD_CONFIG_OFFSET 0x1120
+#define CMD_CLK_GATE_CTL_OFFSET 0x6004
+
+#define CMD_DESC_DW0_VAL 0x500012
+
+/* Address offset for virtual queue registers */
+#define CMD_Q_STATUS_INCR 0x1000
+
+/* Bit masks */
+#define CMD_CONFIG_REQID 0
+#define CMD_TIMEOUT_DISABLE 0
+#define CMD_CLK_DYN_GATING_DIS 0
+#define CMD_CLK_SW_GATE_MODE 0
+#define CMD_CLK_GATE_CTL 0
+#define CMD_QUEUE_PRIO GENMASK(2, 1)
+#define CMD_CONFIG_VHB_EN BIT(0)
+#define CMD_CLK_DYN_GATING_EN BIT(0)
+#define CMD_CLK_HW_GATE_MODE BIT(0)
+#define CMD_CLK_GATE_ON_DELAY BIT(12)
+#define CMD_CLK_GATE_OFF_DELAY BIT(12)
+
+#define CMD_CLK_GATE_CONFIG (CMD_CLK_GATE_CTL | \
+ CMD_CLK_HW_GATE_MODE | \
+ CMD_CLK_GATE_ON_DELAY | \
+ CMD_CLK_DYN_GATING_EN | \
+ CMD_CLK_GATE_OFF_DELAY)
+
+#define CMD_Q_LEN 32
+#define CMD_Q_RUN BIT(0)
+#define CMD_Q_HALT BIT(1)
+#define CMD_Q_MEM_LOCATION BIT(2)
+#define CMD_Q_SIZE_MASK GENMASK(4, 0)
+#define CMD_Q_SIZE GENMASK(7, 3)
+#define CMD_Q_SHIFT GENMASK(1, 0)
+#define QUEUE_SIZE_VAL ((ffs(CMD_Q_LEN) - 2) & \
+ CMD_Q_SIZE_MASK)
+#define Q_PTR_MASK (2 << (QUEUE_SIZE_VAL + 5) - 1)
+#define Q_DESC_SIZE sizeof(struct ptdma_desc)
+#define Q_SIZE(n) (CMD_Q_LEN * (n))
+
+#define INT_COMPLETION BIT(0)
+#define INT_ERROR BIT(1)
+#define INT_QUEUE_STOPPED BIT(2)
+#define INT_EMPTY_QUEUE BIT(3)
+#define SUPPORTED_INTERRUPTS (INT_COMPLETION | INT_ERROR)
+
+/****** Local Storage Block ******/
+#define LSB_START 0
+#define LSB_END 127
+#define LSB_COUNT (LSB_END - LSB_START + 1)
+
+#define PT_DMAPOOL_MAX_SIZE 64
+#define PT_DMAPOOL_ALIGN BIT(5)
+
+#define PT_PASSTHRU_BLOCKSIZE 512
+
+struct pt_device;
+
+struct pt_tasklet_data {
+ struct completion completion;
+ struct pt_cmd *cmd;
+};
+
+/*
+ * struct pt_passthru_engine - pass-through operation
+ * without performing DMA mapping
+ * @mask: mask to be applied to data
+ * @mask_len: length in bytes of mask
+ * @src_dma: data to be used for this operation
+ * @dst_dma: data produced by this operation
+ * @src_len: length in bytes of data used for this operation
+ *
+ * Variables required to be set when calling pt_enqueue_cmd():
+ * - bit_mod, byte_swap, src, dst, src_len
+ * - mask, mask_len if bit_mod is not PT_PASSTHRU_BITWISE_NOOP
+ */
+struct pt_passthru_engine {
+ dma_addr_t mask;
+ u32 mask_len; /* In bytes */
+
+ dma_addr_t src_dma, dst_dma;
+ u64 src_len; /* In bytes */
+};
+
+/*
+ * struct pt_cmd - PTDMA operation request
+ * @entry: list element
+ * @work: work element used for callbacks
+ * @pt: PT device to be run on
+ * @ret: operation return code
+ * @flags: cmd processing flags
+ * @engine: PTDMA operation to perform (passthru)
+ * @engine_error: PT engine return code
+ * @passthru: engine specific structures, refer to specific engine struct below
+ * @callback: operation completion callback function
+ * @data: parameter value to be supplied to the callback function
+ *
+ * Variables required to be set when calling pt_enqueue_cmd():
+ * - engine, callback
+ * - See the operation structures below for what is required for each
+ * operation.
+ */
+struct pt_cmd {
+ struct list_head entry;
+ struct work_struct work;
+ struct pt_device *pt;
+ int ret;
+ u32 engine;
+ u32 engine_error;
+ struct pt_passthru_engine passthru;
+ /* Completion callback support */
+ void (*pt_cmd_callback)(void *data, int err);
+ void *data;
+};
+
+struct pt_cmd_queue {
+ struct pt_device *pt;
+
+ /* Queue dma pool */
+ struct dma_pool *dma_pool;
+
+ /* Queue base address (not neccessarily aligned)*/
+ struct ptdma_desc *qbase;
+
+ /* Aligned queue start address (per requirement) */
+ struct mutex q_mutex ____cacheline_aligned;
+ unsigned int qidx;
+
+ unsigned int qsize;
+ dma_addr_t qbase_dma;
+ dma_addr_t qdma_tail;
+
+ unsigned int active;
+ unsigned int suspended;
+
+ /* Register addresses for queue */
+ void __iomem *reg_control;
+ void __iomem *reg_tail_lo;
+ void __iomem *reg_head_lo;
+ void __iomem *reg_int_enable;
+ void __iomem *reg_interrupt_status;
+ void __iomem *reg_status;
+ void __iomem *reg_int_status;
+ void __iomem *reg_dma_status;
+ void __iomem *reg_dma_read_status;
+ void __iomem *reg_dma_write_status;
+ u32 qcontrol; /* Cached control register */
+
+ /* Status values from job */
+ u32 int_status;
+ u32 q_status;
+ u32 q_int_status;
+ u32 cmd_error;
+} ____cacheline_aligned;
+
+struct pt_device {
+ struct list_head entry;
+
+ unsigned int ord;
+ char name[MAX_PT_NAME_LEN];
+
+ struct device *dev;
+
+ /* Bus specific device information */
+ struct pt_msix *pt_msix;
+
+ struct pt_dev_vdata *dev_vdata;
+
+ unsigned int pt_irq;
+
+ /* I/O area used for device communication */
+ void __iomem *io_regs;
+
+ spinlock_t cmd_lock ____cacheline_aligned;
+ unsigned int cmd_count;
+ struct list_head cmd;
+
+ /*
+ * The command queue. This represent the queue available on the
+ * PTDMA that are available for processing cmds
+ */
+ struct pt_cmd_queue cmd_q;
+
+ wait_queue_head_t lsb_queue;
+
+ struct pt_tasklet_data tdata;
+};
+
+/*
+ * descriptor for PTDMA commands
+ * 8 32-bit words:
+ * word 0: function; engine; control bits
+ * word 1: length of source data
+ * word 2: low 32 bits of source pointer
+ * word 3: upper 16 bits of source pointer; source memory type
+ * word 4: low 32 bits of destination pointer
+ * word 5: upper 16 bits of destination pointer; destination memory type
+ * word 6: reserved 32 bits
+ * word 7: reserved 32 bits
+ */
+
+#define DWORD0_SOC BIT(0)
+#define DWORD0_IOC BIT(1)
+
+struct dword3 {
+ unsigned int src_hi:16;
+ unsigned int src_mem:2;
+ unsigned int lsb_cxt_id:8;
+ unsigned int rsvd1:5;
+ unsigned int fixed:1;
+};
+
+struct dword5 {
+ unsigned int dst_hi:16;
+ unsigned int dst_mem:2;
+ unsigned int rsvd1:13;
+ unsigned int fixed:1;
+};
+
+struct ptdma_desc {
+ u32 dw0;
+ u32 length;
+ u32 src_lo;
+ struct dword3 dw3;
+ u32 dst_lo;
+ struct dword5 dw5;
+ __le32 rsvd1;
+ __le32 rsvd2;
+};
+
+/* Structure to hold PT device data */
+struct pt_dev_vdata {
+ const unsigned int bar;
+};
+
+int pt_core_init(struct pt_device *pt);
+void pt_core_destroy(struct pt_device *pt);
+
+int pt_core_perform_passthru(struct pt_cmd_queue *cmd_q,
+ struct pt_passthru_engine *pt_engine);
+
+void pt_start_queue(struct pt_cmd_queue *cmd_q);
+void pt_stop_queue(struct pt_cmd_queue *cmd_q);
+
+#endif
--
2.7.4