From: Sanjay R Mehta <sanju.me...@amd.com>

This driver add support for AMD PTDMA controller.  This device
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.me...@amd.com>
---
 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 | 306 +++++++++++++++++++++++++++++++++++++++
 drivers/dma/ptdma/ptdma-pci.c | 253 +++++++++++++++++++++++++++++++++
 drivers/dma/ptdma/ptdma.h     | 324 ++++++++++++++++++++++++++++++++++++++++++
 8 files changed, 913 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 68f21d4..8396e92 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -934,6 +934,12 @@ S: Supported
 F:     arch/arm64/boot/dts/amd/amd-seattle-xgbe*.dtsi
 F:     drivers/net/ethernet/amd/xgbe/
 
++AMD PTDMA DRIVER
++M:    Sanjay R Mehta <sanju.me...@amd.com>
++L:    dmaeng...@vger.kernel.org
++S:    Maintained
++F:    drivers/dma/ptdma/
+
 ANALOG DEVICES INC AD5686 DRIVER
 M:     Michael Hennerich <michael.henner...@analog.com>
 L:     linux...@vger.kernel.org
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index de41d79..8f661ff 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -737,6 +737,8 @@ source "drivers/dma/ti/Kconfig"
 
 source "drivers/dma/fsl-dpaa2-qdma/Kconfig"
 
+source "drivers/dma/ptdma/Kconfig"
+
 # clients
 comment "DMA Clients"
        depends on DMA_ENGINE
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index e60f813..2785756 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -83,6 +83,7 @@ obj-$(CONFIG_XGENE_DMA) += xgene-dma.o
 obj-$(CONFIG_ZX_DMA) += zx_dma.o
 obj-$(CONFIG_ST_FDMA) += st_fdma.o
 obj-$(CONFIG_FSL_DPAA2_QDMA) += fsl-dpaa2-qdma/
+obj-$(CONFIG_AMD_PTDMA) += ptdma/
 
 obj-y += mediatek/
 obj-y += qcom/
diff --git a/drivers/dma/ptdma/Kconfig b/drivers/dma/ptdma/Kconfig
new file mode 100644
index 0000000..f93f9c2
--- /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 & performs high bandwidth memory to
+         memory and IO copy operation and performs DMA transfer through
+         queue based descriptor management. This DMA controller is intended
+         to use with AMD Non-Transparent Bridge devices and not for general
+         purpose slave 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..d6dca5a
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma-dev.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2020 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.me...@amd.com>
+ * Author: Gary R Hook <gary.h...@amd.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.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)
+{
+       __le32 *mp;
+       u32 *dp;
+       u32 tail;
+       int     i;
+       int ret = 0;
+
+       if (desc->dw0.soc) {
+               desc->dw0.ioc = 1;
+               desc->dw0.soc = 0;
+       }
+       mutex_lock(&cmd_q->q_mutex);
+
+       mp = (__le32 *)&cmd_q->qbase[cmd_q->qidx];
+       dp = (u32 *)desc;
+       for (i = 0; i < 8; i++)
+               mp[i] = cpu_to_le32(dp[i]); /* handle endianness */
+
+       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 ret;
+}
+
+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, Q_DESC_SIZE);
+
+       desc.dw0.val = 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(0x0, 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 = (struct pt_device *)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)
+{
+       struct device *dev = pt->dev;
+       struct pt_cmd_queue *cmd_q = &pt->cmd_q;
+       struct dma_pool *dma_pool;
+       char dma_pool_name[MAX_DMAPOOL_NAME_LEN];
+       int ret;
+       u32 dma_addr_lo, dma_addr_hi;
+
+       /* 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");
+               ret = -ENOMEM;
+               return ret;
+       }
+
+       /* 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);
+
+       dev_dbg(dev, "queue available\n");
+
+       /* 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) {
+               dev_err(dev, "unable to allocate an IRQ\n");
+               goto e_pool;
+       }
+
+       /* Update the device registers with queue information.  */
+
+       cmd_q->qcontrol &= ~(CMD_Q_SIZE << CMD_Q_SHIFT);
+       cmd_q->qcontrol |= QUEUE_SIZE_VAL << CMD_Q_SHIFT;
+
+       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);
+
+       dev_dbg(dev, "Enabling interrupts...\n");
+       pt_core_enable_queue_interrupts(pt);
+
+       dev_dbg(dev, "PTDMA device %s registration successful...\n", pt->name);
+
+       return 0;
+
+e_dma_alloc:
+       dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase, cmd_q->qbase_dma);
+
+e_pool:
+       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..11b5e2a
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma-pci.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2020 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.me...@amd.com>
+ * Author: Tom Lendacky <thomas.lenda...@amd.com>
+ * Author: Gary R Hook <gary.h...@amd.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/dma-mapping.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/delay.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_notice(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_notice(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) {
+               dev_notice(dev, "PTDMA initialization failed\n");
+               goto e_err;
+       }
+
+       dev_notice(dev, "PTDMA enabled\n");
+
+       return 0;
+
+e_err:
+       dev_notice(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,
+               .version = PT_VERSION(5, 0),
+       },
+};
+
+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.me...@amd.com>");
+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..6b3b3cc
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma.h
@@ -0,0 +1,324 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AMD Passthru DMA device driver
+ * -- Based on the CCP driver
+ *
+ * Copyright (C) 2016,2020 Advanced Micro Devices, Inc.
+ *
+ * Author: Sanjay R Mehta <sanju.me...@amd.com>
+ * Author: Tom Lendacky <thomas.lenda...@amd.com>
+ * Author: Gary R Hook <gary.h...@amd.com>
+ */
+
+#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))
+#define        PT_VERSION(v, r)                ((unsigned int)(((v) << 
PT_VSIZE) \
+                                                      | ((r) & PT_VMASK)))
+
+/* 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_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                     GENMASK(4, 0)
+#define CMD_Q_SHIFT                    GENMASK(1, 0)
+#define QUEUE_SIZE_VAL                 ((ffs(CMD_Q_LEN) - 2) & \
+                                                                 CMD_Q_SIZE)
+#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: data to be used for this operation
+ * @dst: data produced by this operation
+ * @src_len: length in bytes of data used for this operation
+ * @final: indicate final pass-through 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 */
+
+       u32 final;
+};
+
+/*
+ * 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
+ */
+
+union dword0 {
+       struct {
+               unsigned int soc:1;
+               unsigned int ioc:1;
+               unsigned int rsvd1:1;
+               unsigned int init:1;
+               unsigned int eom:1;
+               unsigned int function:15;
+               unsigned int engine:4;
+               unsigned int prot:1;
+               unsigned int rsvd2:7;
+       };
+       u32 val;
+};
+
+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 {
+       union dword0 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;
+       const unsigned int version;
+};
+
+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

Reply via email to