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path: root/drivers/dma/ptdma/ptdma-dev.c
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Diffstat (limited to 'drivers/dma/ptdma/ptdma-dev.c')
-rw-r--r--drivers/dma/ptdma/ptdma-dev.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/dma/ptdma/ptdma-dev.c b/drivers/dma/ptdma/ptdma-dev.c
new file mode 100644
index 000000000000..8a6bf291a73f
--- /dev/null
+++ b/drivers/dma/ptdma/ptdma-dev.c
@@ -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@amd.com>
+ * Author: Gary R Hook <gary.hook@amd.com>
+ */
+
+#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];
+ 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, desc, 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_control + 0x0004);
+
+ /* 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;
+ cmd_q->total_pt_ops++;
+ 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_control + 0x000C);
+}
+
+static inline void pt_core_enable_queue_interrupts(struct pt_device *pt)
+{
+ iowrite32(SUPPORTED_INTERRUPTS, pt->cmd_q.reg_control + 0x000C);
+}
+
+static void pt_do_cmd_complete(unsigned long data)
+{
+ struct pt_tasklet_data *tdata = (struct pt_tasklet_data *)data;
+ struct pt_cmd *cmd = tdata->cmd;
+ struct pt_cmd_queue *cmd_q = &cmd->pt->cmd_q;
+ u32 tail;
+
+ if (cmd_q->cmd_error) {
+ /*
+ * Log the error and flush the queue by
+ * moving the head pointer
+ */
+ tail = lower_32_bits(cmd_q->qdma_tail + cmd_q->qidx * Q_DESC_SIZE);
+ pt_log_error(cmd_q->pt, cmd_q->cmd_error);
+ iowrite32(tail, cmd_q->reg_control + 0x0008);
+ }
+
+ cmd->pt_cmd_callback(cmd->data, cmd->ret);
+}
+
+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);
+ pt->total_interrupts++;
+ status = ioread32(cmd_q->reg_control + 0x0010);
+ if (status) {
+ cmd_q->int_status = status;
+ cmd_q->q_status = ioread32(cmd_q->reg_control + 0x0100);
+ cmd_q->q_int_status = ioread32(cmd_q->reg_control + 0x0104);
+
+ /* 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_control + 0x0010);
+ pt_core_enable_queue_interrupts(pt);
+ pt_do_cmd_complete((ulong)&pt->tdata);
+ }
+ return IRQ_HANDLED;
+}
+
+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", dev_name(pt->dev));
+
+ dma_pool = dma_pool_create(dma_pool_name, dev,
+ PT_DMAPOOL_MAX_SIZE,
+ PT_DMAPOOL_ALIGN, 0);
+ if (!dma_pool)
+ 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;
+
+ /* 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_control + 0x0104);
+ ioread32(cmd_q->reg_control + 0x0100);
+
+ /* Clear the interrupt status */
+ iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_control + 0x0010);
+
+ /* Request an irq */
+ ret = request_irq(pt->pt_irq, pt_core_irq_handler, 0, dev_name(pt->dev), 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_control + 0x0004);
+ iowrite32((u32)dma_addr_lo, cmd_q->reg_control + 0x0008);
+
+ 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);
+
+ /* Register the DMA engine support */
+ ret = pt_dmaengine_register(pt);
+ if (ret)
+ goto e_dmaengine;
+
+ /* Set up debugfs entries */
+ ptdma_debugfs_setup(pt);
+
+ return 0;
+
+e_dmaengine:
+ free_irq(pt->pt_irq, pt);
+
+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;
+
+ /* Unregister the DMA engine */
+ pt_dmaengine_unregister(pt);
+
+ /* 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_control + 0x0010);
+ ioread32(cmd_q->reg_control + 0x0104);
+ ioread32(cmd_q->reg_control + 0x0100);
+
+ 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);
+ }
+}