diff options
Diffstat (limited to 'drivers/dma/ptdma')
-rw-r--r-- | drivers/dma/ptdma/Kconfig | 13 | ||||
-rw-r--r-- | drivers/dma/ptdma/Makefile | 10 | ||||
-rw-r--r-- | drivers/dma/ptdma/ptdma-debugfs.c | 106 | ||||
-rw-r--r-- | drivers/dma/ptdma/ptdma-dev.c | 309 | ||||
-rw-r--r-- | drivers/dma/ptdma/ptdma-dmaengine.c | 413 | ||||
-rw-r--r-- | drivers/dma/ptdma/ptdma-pci.c | 243 | ||||
-rw-r--r-- | drivers/dma/ptdma/ptdma.h | 337 |
7 files changed, 1431 insertions, 0 deletions
diff --git a/drivers/dma/ptdma/Kconfig b/drivers/dma/ptdma/Kconfig new file mode 100644 index 000000000..b430edd70 --- /dev/null +++ b/drivers/dma/ptdma/Kconfig @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0-only +config AMD_PTDMA + tristate "AMD PassThru DMA Engine" + depends on X86_64 && PCI + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + 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 000000000..ce5410268 --- /dev/null +++ b/drivers/dma/ptdma/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# AMD Passthru DMA driver +# + +obj-$(CONFIG_AMD_PTDMA) += ptdma.o + +ptdma-objs := ptdma-dev.o ptdma-dmaengine.o ptdma-debugfs.o + +ptdma-$(CONFIG_PCI) += ptdma-pci.o diff --git a/drivers/dma/ptdma/ptdma-debugfs.c b/drivers/dma/ptdma/ptdma-debugfs.c new file mode 100644 index 000000000..c8307d304 --- /dev/null +++ b/drivers/dma/ptdma/ptdma-debugfs.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Passthrough 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/debugfs.h> +#include <linux/seq_file.h> + +#include "ptdma.h" + +/* DebugFS helpers */ +#define RI_VERSION_NUM 0x0000003F + +#define RI_NUM_VQM 0x00078000 +#define RI_NVQM_SHIFT 15 + +static int pt_debugfs_info_show(struct seq_file *s, void *p) +{ + struct pt_device *pt = s->private; + unsigned int regval; + + seq_printf(s, "Device name: %s\n", dev_name(pt->dev)); + seq_printf(s, " # Queues: %d\n", 1); + seq_printf(s, " # Cmds: %d\n", pt->cmd_count); + + regval = ioread32(pt->io_regs + CMD_PT_VERSION); + + seq_printf(s, " Version: %d\n", regval & RI_VERSION_NUM); + seq_puts(s, " Engines:"); + seq_puts(s, "\n"); + seq_printf(s, " Queues: %d\n", (regval & RI_NUM_VQM) >> RI_NVQM_SHIFT); + + return 0; +} + +/* + * Return a formatted buffer containing the current + * statistics of queue for PTDMA + */ +static int pt_debugfs_stats_show(struct seq_file *s, void *p) +{ + struct pt_device *pt = s->private; + + seq_printf(s, "Total Interrupts Handled: %ld\n", pt->total_interrupts); + + return 0; +} + +static int pt_debugfs_queue_show(struct seq_file *s, void *p) +{ + struct pt_cmd_queue *cmd_q = s->private; + unsigned int regval; + + if (!cmd_q) + return 0; + + seq_printf(s, " Pass-Thru: %ld\n", cmd_q->total_pt_ops); + + regval = ioread32(cmd_q->reg_control + 0x000C); + + seq_puts(s, " Enabled Interrupts:"); + if (regval & INT_EMPTY_QUEUE) + seq_puts(s, " EMPTY"); + if (regval & INT_QUEUE_STOPPED) + seq_puts(s, " STOPPED"); + if (regval & INT_ERROR) + seq_puts(s, " ERROR"); + if (regval & INT_COMPLETION) + seq_puts(s, " COMPLETION"); + seq_puts(s, "\n"); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_info); +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_queue); +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_stats); + +void ptdma_debugfs_setup(struct pt_device *pt) +{ + struct pt_cmd_queue *cmd_q; + struct dentry *debugfs_q_instance; + + if (!debugfs_initialized()) + return; + + debugfs_create_file("info", 0400, pt->dma_dev.dbg_dev_root, pt, + &pt_debugfs_info_fops); + + debugfs_create_file("stats", 0400, pt->dma_dev.dbg_dev_root, pt, + &pt_debugfs_stats_fops); + + cmd_q = &pt->cmd_q; + + debugfs_q_instance = + debugfs_create_dir("q", pt->dma_dev.dbg_dev_root); + + debugfs_create_file("stats", 0400, debugfs_q_instance, cmd_q, + &pt_debugfs_queue_fops); +} diff --git a/drivers/dma/ptdma/ptdma-dev.c b/drivers/dma/ptdma/ptdma-dev.c new file mode 100644 index 000000000..a2bf13ff1 --- /dev/null +++ b/drivers/dma/ptdma/ptdma-dev.c @@ -0,0 +1,309 @@ +// 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; + 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); + } +} diff --git a/drivers/dma/ptdma/ptdma-dmaengine.c b/drivers/dma/ptdma/ptdma-dmaengine.c new file mode 100644 index 000000000..1aa65e5de --- /dev/null +++ b/drivers/dma/ptdma/ptdma-dmaengine.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Passthrough 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 "ptdma.h" +#include "../dmaengine.h" +#include "../virt-dma.h" + +static inline struct pt_dma_chan *to_pt_chan(struct dma_chan *dma_chan) +{ + return container_of(dma_chan, struct pt_dma_chan, vc.chan); +} + +static inline struct pt_dma_desc *to_pt_desc(struct virt_dma_desc *vd) +{ + return container_of(vd, struct pt_dma_desc, vd); +} + +static void pt_free_chan_resources(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + + vchan_free_chan_resources(&chan->vc); +} + +static void pt_synchronize(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + + vchan_synchronize(&chan->vc); +} + +static void pt_do_cleanup(struct virt_dma_desc *vd) +{ + struct pt_dma_desc *desc = to_pt_desc(vd); + struct pt_device *pt = desc->pt; + + kmem_cache_free(pt->dma_desc_cache, desc); +} + +static int pt_dma_start_desc(struct pt_dma_desc *desc) +{ + struct pt_passthru_engine *pt_engine; + struct pt_device *pt; + struct pt_cmd *pt_cmd; + struct pt_cmd_queue *cmd_q; + + desc->issued_to_hw = 1; + + pt_cmd = &desc->pt_cmd; + pt = pt_cmd->pt; + cmd_q = &pt->cmd_q; + pt_engine = &pt_cmd->passthru; + + pt->tdata.cmd = pt_cmd; + + /* Execute the command */ + pt_cmd->ret = pt_core_perform_passthru(cmd_q, pt_engine); + + return 0; +} + +static struct pt_dma_desc *pt_next_dma_desc(struct pt_dma_chan *chan) +{ + /* Get the next DMA descriptor on the active list */ + struct virt_dma_desc *vd = vchan_next_desc(&chan->vc); + + return vd ? to_pt_desc(vd) : NULL; +} + +static struct pt_dma_desc *pt_handle_active_desc(struct pt_dma_chan *chan, + struct pt_dma_desc *desc) +{ + struct dma_async_tx_descriptor *tx_desc; + struct virt_dma_desc *vd; + unsigned long flags; + + /* Loop over descriptors until one is found with commands */ + do { + if (desc) { + if (!desc->issued_to_hw) { + /* No errors, keep going */ + if (desc->status != DMA_ERROR) + return desc; + } + + tx_desc = &desc->vd.tx; + vd = &desc->vd; + } else { + tx_desc = NULL; + } + + spin_lock_irqsave(&chan->vc.lock, flags); + + if (desc) { + if (desc->status != DMA_COMPLETE) { + if (desc->status != DMA_ERROR) + desc->status = DMA_COMPLETE; + + dma_cookie_complete(tx_desc); + dma_descriptor_unmap(tx_desc); + list_del(&desc->vd.node); + } else { + /* Don't handle it twice */ + tx_desc = NULL; + } + } + + desc = pt_next_dma_desc(chan); + + spin_unlock_irqrestore(&chan->vc.lock, flags); + + if (tx_desc) { + dmaengine_desc_get_callback_invoke(tx_desc, NULL); + dma_run_dependencies(tx_desc); + vchan_vdesc_fini(vd); + } + } while (desc); + + return NULL; +} + +static void pt_cmd_callback(void *data, int err) +{ + struct pt_dma_desc *desc = data; + struct dma_chan *dma_chan; + struct pt_dma_chan *chan; + int ret; + + if (err == -EINPROGRESS) + return; + + dma_chan = desc->vd.tx.chan; + chan = to_pt_chan(dma_chan); + + if (err) + desc->status = DMA_ERROR; + + while (true) { + /* Check for DMA descriptor completion */ + desc = pt_handle_active_desc(chan, desc); + + /* Don't submit cmd if no descriptor or DMA is paused */ + if (!desc) + break; + + ret = pt_dma_start_desc(desc); + if (!ret) + break; + + desc->status = DMA_ERROR; + } +} + +static struct pt_dma_desc *pt_alloc_dma_desc(struct pt_dma_chan *chan, + unsigned long flags) +{ + struct pt_dma_desc *desc; + + desc = kmem_cache_zalloc(chan->pt->dma_desc_cache, GFP_NOWAIT); + if (!desc) + return NULL; + + vchan_tx_prep(&chan->vc, &desc->vd, flags); + + desc->pt = chan->pt; + desc->pt->cmd_q.int_en = !!(flags & DMA_PREP_INTERRUPT); + desc->issued_to_hw = 0; + desc->status = DMA_IN_PROGRESS; + + return desc; +} + +static struct pt_dma_desc *pt_create_desc(struct dma_chan *dma_chan, + dma_addr_t dst, + dma_addr_t src, + unsigned int len, + unsigned long flags) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + struct pt_passthru_engine *pt_engine; + struct pt_dma_desc *desc; + struct pt_cmd *pt_cmd; + + desc = pt_alloc_dma_desc(chan, flags); + if (!desc) + return NULL; + + pt_cmd = &desc->pt_cmd; + pt_cmd->pt = chan->pt; + pt_engine = &pt_cmd->passthru; + pt_cmd->engine = PT_ENGINE_PASSTHRU; + pt_engine->src_dma = src; + pt_engine->dst_dma = dst; + pt_engine->src_len = len; + pt_cmd->pt_cmd_callback = pt_cmd_callback; + pt_cmd->data = desc; + + desc->len = len; + + return desc; +} + +static struct dma_async_tx_descriptor * +pt_prep_dma_memcpy(struct dma_chan *dma_chan, dma_addr_t dst, + dma_addr_t src, size_t len, unsigned long flags) +{ + struct pt_dma_desc *desc; + + desc = pt_create_desc(dma_chan, dst, src, len, flags); + if (!desc) + return NULL; + + return &desc->vd.tx; +} + +static struct dma_async_tx_descriptor * +pt_prep_dma_interrupt(struct dma_chan *dma_chan, unsigned long flags) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + struct pt_dma_desc *desc; + + desc = pt_alloc_dma_desc(chan, flags); + if (!desc) + return NULL; + + return &desc->vd.tx; +} + +static void pt_issue_pending(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + struct pt_dma_desc *desc; + unsigned long flags; + bool engine_is_idle = true; + + spin_lock_irqsave(&chan->vc.lock, flags); + + desc = pt_next_dma_desc(chan); + if (desc) + engine_is_idle = false; + + vchan_issue_pending(&chan->vc); + + desc = pt_next_dma_desc(chan); + + spin_unlock_irqrestore(&chan->vc.lock, flags); + + /* If there was nothing active, start processing */ + if (engine_is_idle && desc) + pt_cmd_callback(desc, 0); +} + +static enum dma_status +pt_tx_status(struct dma_chan *c, dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct pt_device *pt = to_pt_chan(c)->pt; + struct pt_cmd_queue *cmd_q = &pt->cmd_q; + + pt_check_status_trans(pt, cmd_q); + return dma_cookie_status(c, cookie, txstate); +} + +static int pt_pause(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + unsigned long flags; + + spin_lock_irqsave(&chan->vc.lock, flags); + pt_stop_queue(&chan->pt->cmd_q); + spin_unlock_irqrestore(&chan->vc.lock, flags); + + return 0; +} + +static int pt_resume(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + struct pt_dma_desc *desc = NULL; + unsigned long flags; + + spin_lock_irqsave(&chan->vc.lock, flags); + pt_start_queue(&chan->pt->cmd_q); + desc = pt_next_dma_desc(chan); + spin_unlock_irqrestore(&chan->vc.lock, flags); + + /* If there was something active, re-start */ + if (desc) + pt_cmd_callback(desc, 0); + + return 0; +} + +static int pt_terminate_all(struct dma_chan *dma_chan) +{ + struct pt_dma_chan *chan = to_pt_chan(dma_chan); + unsigned long flags; + struct pt_cmd_queue *cmd_q = &chan->pt->cmd_q; + LIST_HEAD(head); + + iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_control + 0x0010); + spin_lock_irqsave(&chan->vc.lock, flags); + vchan_get_all_descriptors(&chan->vc, &head); + spin_unlock_irqrestore(&chan->vc.lock, flags); + + vchan_dma_desc_free_list(&chan->vc, &head); + vchan_free_chan_resources(&chan->vc); + + return 0; +} + +int pt_dmaengine_register(struct pt_device *pt) +{ + struct pt_dma_chan *chan; + struct dma_device *dma_dev = &pt->dma_dev; + char *cmd_cache_name; + char *desc_cache_name; + int ret; + + pt->pt_dma_chan = devm_kzalloc(pt->dev, sizeof(*pt->pt_dma_chan), + GFP_KERNEL); + if (!pt->pt_dma_chan) + return -ENOMEM; + + cmd_cache_name = devm_kasprintf(pt->dev, GFP_KERNEL, + "%s-dmaengine-cmd-cache", + dev_name(pt->dev)); + if (!cmd_cache_name) + return -ENOMEM; + + desc_cache_name = devm_kasprintf(pt->dev, GFP_KERNEL, + "%s-dmaengine-desc-cache", + dev_name(pt->dev)); + if (!desc_cache_name) { + ret = -ENOMEM; + goto err_cache; + } + + pt->dma_desc_cache = kmem_cache_create(desc_cache_name, + sizeof(struct pt_dma_desc), 0, + SLAB_HWCACHE_ALIGN, NULL); + if (!pt->dma_desc_cache) { + ret = -ENOMEM; + goto err_cache; + } + + dma_dev->dev = pt->dev; + dma_dev->src_addr_widths = DMA_SLAVE_BUSWIDTH_64_BYTES; + dma_dev->dst_addr_widths = DMA_SLAVE_BUSWIDTH_64_BYTES; + dma_dev->directions = DMA_MEM_TO_MEM; + dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; + dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); + dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask); + + /* + * PTDMA is intended to be used with the AMD NTB devices, hence + * marking it as DMA_PRIVATE. + */ + dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); + + INIT_LIST_HEAD(&dma_dev->channels); + + chan = pt->pt_dma_chan; + chan->pt = pt; + + /* Set base and prep routines */ + dma_dev->device_free_chan_resources = pt_free_chan_resources; + dma_dev->device_prep_dma_memcpy = pt_prep_dma_memcpy; + dma_dev->device_prep_dma_interrupt = pt_prep_dma_interrupt; + dma_dev->device_issue_pending = pt_issue_pending; + dma_dev->device_tx_status = pt_tx_status; + dma_dev->device_pause = pt_pause; + dma_dev->device_resume = pt_resume; + dma_dev->device_terminate_all = pt_terminate_all; + dma_dev->device_synchronize = pt_synchronize; + + chan->vc.desc_free = pt_do_cleanup; + vchan_init(&chan->vc, dma_dev); + + dma_set_mask_and_coherent(pt->dev, DMA_BIT_MASK(64)); + + ret = dma_async_device_register(dma_dev); + if (ret) + goto err_reg; + + return 0; + +err_reg: + kmem_cache_destroy(pt->dma_desc_cache); + +err_cache: + kmem_cache_destroy(pt->dma_cmd_cache); + + return ret; +} + +void pt_dmaengine_unregister(struct pt_device *pt) +{ + struct dma_device *dma_dev = &pt->dma_dev; + + dma_async_device_unregister(dma_dev); + + kmem_cache_destroy(pt->dma_desc_cache); + kmem_cache_destroy(pt->dma_cmd_cache); +} diff --git a/drivers/dma/ptdma/ptdma-pci.c b/drivers/dma/ptdma/ptdma-pci.c new file mode 100644 index 000000000..22739ff0c --- /dev/null +++ b/drivers/dma/ptdma/ptdma-pci.c @@ -0,0 +1,243 @@ +// 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: Tom Lendacky <thomas.lendacky@amd.com> + * Author: Gary R Hook <gary.hook@amd.com> + */ + +#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" + +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; + + INIT_LIST_HEAD(&pt->cmd); + + 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; + + return 0; + +e_err: + dev_err(dev, "initialization failed ret = %d\n", ret); + + 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@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 000000000..21b4bf895 --- /dev/null +++ b/drivers/dma/ptdma/ptdma.h @@ -0,0 +1,337 @@ +/* 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: Tom Lendacky <thomas.lendacky@amd.com> + * Author: Gary R Hook <gary.hook@amd.com> + */ + +#ifndef __PT_DEV_H__ +#define __PT_DEV_H__ + +#include <linux/device.h> +#include <linux/dmaengine.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> + +#include "../virt-dma.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 + +/* 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_dma_desc { + struct virt_dma_desc vd; + struct pt_device *pt; + enum dma_status status; + size_t len; + bool issued_to_hw; + struct pt_cmd pt_cmd; +}; + +struct pt_dma_chan { + struct virt_dma_chan vc; + struct pt_device *pt; +}; + +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) */ + spinlock_t q_lock ____cacheline_aligned; + unsigned int qidx; + + unsigned int qsize; + dma_addr_t qbase_dma; + dma_addr_t qdma_tail; + + unsigned int active; + unsigned int suspended; + + /* Interrupt flag */ + bool int_en; + + /* Register addresses for queue */ + void __iomem *reg_control; + u32 qcontrol; /* Cached control register */ + + /* Status values from job */ + u32 int_status; + u32 q_status; + u32 q_int_status; + u32 cmd_error; + /* Queue Statistics */ + unsigned long total_pt_ops; +} ____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; + + /* Support for the DMA Engine capabilities */ + struct dma_device dma_dev; + struct pt_dma_chan *pt_dma_chan; + struct kmem_cache *dma_cmd_cache; + struct kmem_cache *dma_desc_cache; + + wait_queue_head_t lsb_queue; + + /* Device Statistics */ + unsigned long total_interrupts; + + 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_dmaengine_register(struct pt_device *pt); +void pt_dmaengine_unregister(struct pt_device *pt); + +void ptdma_debugfs_setup(struct pt_device *pt); +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_check_status_trans(struct pt_device *pt, struct pt_cmd_queue *cmd_q); +void pt_start_queue(struct pt_cmd_queue *cmd_q); +void pt_stop_queue(struct pt_cmd_queue *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); +} +#endif |