// 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 <[email protected]>
* Author: Gary R Hook <[email protected]>
*/
#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;
unsigned long flags;
if (soc) {
desc->dw0 |= FIELD_PREP(DWORD0_IOC, desc->dw0);
desc->dw0 &= ~DWORD0_SOC;
}
spin_lock_irqsave(&cmd_q->q_lock, flags);
/* 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);
spin_unlock_irqrestore(&cmd_q->q_lock, flags);
return 0;
}
int pt_core_perform_passthru(struct pt_cmd_queue *cmd_q,
struct pt_passthru_engine *pt_engine)
{
struct ptdma_desc desc;
struct pt_device *pt = container_of(cmd_q, struct pt_device, cmd_q);
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);
if (cmd_q->int_en)
pt_core_enable_queue_interrupts(pt);
else
pt_core_disable_queue_interrupts(pt);
return pt_core_execute_cmd(&desc, cmd_q);
}
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);
}
void pt_check_status_trans(struct pt_device *pt, struct pt_cmd_queue *cmd_q)
{
u32 status;
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 completion */
iowrite32(status, cmd_q->reg_control + 0x0010);
pt_do_cmd_complete((ulong)&pt->tdata);
}
}
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;
pt_core_disable_queue_interrupts(pt);
pt->total_interrupts++;
pt_check_status_trans(pt, cmd_q);
pt_core_enable_queue_interrupts(pt);
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;
spin_lock_init(&cmd_q->q_lock);
/* 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_destroy_pool;
}
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) {
dev_err(dev, "unable to allocate an IRQ\n");
goto e_free_dma;
}
/* 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_free_irq;
/* Set up debugfs entries */
ptdma_debugfs_setup(pt);
return 0;
e_free_irq:
free_irq(pt->pt_irq, pt);
e_free_dma:
dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase, cmd_q->qbase_dma);
e_destroy_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;
/* 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);
}
}
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