On Fri, May 10, 2024 at 01:50:48PM +0530, Basavaraj Natikar wrote: > Add support for AMD AE4DMA 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. > > Reviewed-by: Raju Rangoju <Raju.Rangoju@xxxxxxx> > Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > --- > MAINTAINERS | 6 + > drivers/dma/amd/Kconfig | 1 + > drivers/dma/amd/Makefile | 1 + > drivers/dma/amd/ae4dma/Kconfig | 13 ++ > drivers/dma/amd/ae4dma/Makefile | 10 ++ > drivers/dma/amd/ae4dma/ae4dma-dev.c | 206 ++++++++++++++++++++++++++++ > drivers/dma/amd/ae4dma/ae4dma-pci.c | 195 ++++++++++++++++++++++++++ > drivers/dma/amd/ae4dma/ae4dma.h | 77 +++++++++++ > drivers/dma/amd/common/amd_dma.h | 26 ++++ > 9 files changed, 535 insertions(+) > create mode 100644 drivers/dma/amd/ae4dma/Kconfig > create mode 100644 drivers/dma/amd/ae4dma/Makefile > create mode 100644 drivers/dma/amd/ae4dma/ae4dma-dev.c > create mode 100644 drivers/dma/amd/ae4dma/ae4dma-pci.c > create mode 100644 drivers/dma/amd/ae4dma/ae4dma.h > create mode 100644 drivers/dma/amd/common/amd_dma.h > > diff --git a/MAINTAINERS b/MAINTAINERS > index b190efda33ba..45f2140093b6 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -909,6 +909,12 @@ L: linux-edac@xxxxxxxxxxxxxxx > S: Supported > F: drivers/ras/amd/atl/* > > +AMD AE4DMA DRIVER > +M: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > +L: dmaengine@xxxxxxxxxxxxxxx > +S: Maintained > +F: drivers/dma/amd/ae4dma/ > + > AMD AXI W1 DRIVER > M: Kris Chaplin <kris.chaplin@xxxxxxx> > R: Thomas Delev <thomas.delev@xxxxxxx> > diff --git a/drivers/dma/amd/Kconfig b/drivers/dma/amd/Kconfig > index 8246b463bcf7..8c25a3ed6b94 100644 > --- a/drivers/dma/amd/Kconfig > +++ b/drivers/dma/amd/Kconfig > @@ -3,3 +3,4 @@ > # AMD DMA Drivers > > source "drivers/dma/amd/ptdma/Kconfig" > +source "drivers/dma/amd/ae4dma/Kconfig" > diff --git a/drivers/dma/amd/Makefile b/drivers/dma/amd/Makefile > index dd7257ba7e06..8049b06a9ff5 100644 > --- a/drivers/dma/amd/Makefile > +++ b/drivers/dma/amd/Makefile > @@ -4,3 +4,4 @@ > # > > obj-$(CONFIG_AMD_PTDMA) += ptdma/ > +obj-$(CONFIG_AMD_AE4DMA) += ae4dma/ > diff --git a/drivers/dma/amd/ae4dma/Kconfig b/drivers/dma/amd/ae4dma/Kconfig > new file mode 100644 > index 000000000000..cf8db4dac98d > --- /dev/null > +++ b/drivers/dma/amd/ae4dma/Kconfig > @@ -0,0 +1,13 @@ > +# SPDX-License-Identifier: GPL-2.0 > +config AMD_AE4DMA > + tristate "AMD AE4DMA Engine" > + depends on X86_64 && PCI > + select DMA_ENGINE > + select DMA_VIRTUAL_CHANNELS > + help > + Enable support for the AMD AE4DMA 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/amd/ae4dma/Makefile b/drivers/dma/amd/ae4dma/Makefile > new file mode 100644 > index 000000000000..e918f85a80ec > --- /dev/null > +++ b/drivers/dma/amd/ae4dma/Makefile > @@ -0,0 +1,10 @@ > +# SPDX-License-Identifier: GPL-2.0 > +# > +# AMD AE4DMA driver > +# > + > +obj-$(CONFIG_AMD_AE4DMA) += ae4dma.o > + > +ae4dma-objs := ae4dma-dev.o > + > +ae4dma-$(CONFIG_PCI) += ae4dma-pci.o > diff --git a/drivers/dma/amd/ae4dma/ae4dma-dev.c b/drivers/dma/amd/ae4dma/ae4dma-dev.c > new file mode 100644 > index 000000000000..fc33d2056af2 > --- /dev/null > +++ b/drivers/dma/amd/ae4dma/ae4dma-dev.c > @@ -0,0 +1,206 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * AMD AE4DMA driver > + * > + * Copyright (c) 2024, Advanced Micro Devices, Inc. > + * All Rights Reserved. > + * > + * Author: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > + */ > + > +#include "ae4dma.h" > + > +static unsigned int max_hw_q = 1; > +module_param(max_hw_q, uint, 0444); > +MODULE_PARM_DESC(max_hw_q, "max hw queues supported by engine (any non-zero value, default: 1)"); Does it get from hardware register? you put to global variable. How about system have two difference DMA controllers, one's max_hw_q is 1, the other is 2. > + > +static char *ae4_error_codes[] = { > + "", > + "ERR 01: INVALID HEADER DW0", > + "ERR 02: INVALID STATUS", > + "ERR 03: INVALID LENGTH - 4 BYTE ALIGNMENT", > + "ERR 04: INVALID SRC ADDR - 4 BYTE ALIGNMENT", > + "ERR 05: INVALID DST ADDR - 4 BYTE ALIGNMENT", > + "ERR 06: INVALID ALIGNMENT", > + "ERR 07: INVALID DESCRIPTOR", > +}; > + > +static void ae4_log_error(struct pt_device *d, int e) > +{ > + if (e <= 7) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", ae4_error_codes[e], e); > + else if (e > 7 && e <= 15) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", "INVALID DESCRIPTOR", e); > + else if (e > 15 && e <= 31) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", "INVALID DESCRIPTOR", e); > + else if (e > 31 && e <= 63) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", "INVALID DESCRIPTOR", e); > + else if (e > 63 && e <= 127) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", "PTE ERROR", e); > + else if (e > 127 && e <= 255) > + dev_info(d->dev, "AE4DMA error: %s (0x%x)\n", "PTE ERROR", e); > + else > + dev_info(d->dev, "Unknown AE4DMA error"); > +} > + > +static void ae4_check_status_error(struct ae4_cmd_queue *ae4cmd_q, int idx) > +{ > + struct pt_cmd_queue *cmd_q = &ae4cmd_q->cmd_q; > + struct ae4dma_desc desc; > + u8 status; > + > + memcpy(&desc, &cmd_q->qbase[idx], sizeof(struct ae4dma_desc)); > + /* Synchronize ordering */ > + mb(); does dma_wmb() enough? > + status = desc.dw1.status; > + if (status && status != AE4_DESC_COMPLETED) { > + cmd_q->cmd_error = desc.dw1.err_code; > + if (cmd_q->cmd_error) > + ae4_log_error(cmd_q->pt, cmd_q->cmd_error); > + } > +} > + > +static void ae4_pending_work(struct work_struct *work) > +{ > + struct ae4_cmd_queue *ae4cmd_q = container_of(work, struct ae4_cmd_queue, p_work.work); > + struct pt_cmd_queue *cmd_q = &ae4cmd_q->cmd_q; > + struct pt_cmd *cmd; > + u32 cridx, dridx; > + > + while (true) { > + wait_event_interruptible(ae4cmd_q->q_w, > + ((atomic64_read(&ae4cmd_q->done_cnt)) < > + atomic64_read(&ae4cmd_q->intr_cnt))); wait_event_interruptible_timeout() ? to avoid patental deadlock. > + > + atomic64_inc(&ae4cmd_q->done_cnt); > + > + mutex_lock(&ae4cmd_q->cmd_lock); > + > + cridx = readl(cmd_q->reg_control + 0x0C); > + dridx = atomic_read(&ae4cmd_q->dridx); > + > + while ((dridx != cridx) && !list_empty(&ae4cmd_q->cmd)) { > + cmd = list_first_entry(&ae4cmd_q->cmd, struct pt_cmd, entry); > + list_del(&cmd->entry); > + > + ae4_check_status_error(ae4cmd_q, dridx); > + cmd->pt_cmd_callback(cmd->data, cmd->ret); > + > + atomic64_dec(&ae4cmd_q->q_cmd_count); > + dridx = (dridx + 1) % CMD_Q_LEN; > + atomic_set(&ae4cmd_q->dridx, dridx); > + /* Synchronize ordering */ > + mb(); > + > + complete_all(&ae4cmd_q->cmp); > + } > + > + mutex_unlock(&ae4cmd_q->cmd_lock); > + } > +} > + > +static irqreturn_t ae4_core_irq_handler(int irq, void *data) > +{ > + struct ae4_cmd_queue *ae4cmd_q = data; > + struct pt_cmd_queue *cmd_q; > + struct pt_device *pt; > + u32 status; > + > + cmd_q = &ae4cmd_q->cmd_q; > + pt = cmd_q->pt; > + > + pt->total_interrupts++; > + atomic64_inc(&ae4cmd_q->intr_cnt); > + > + wake_up(&ae4cmd_q->q_w); > + > + status = readl(cmd_q->reg_control + 0x14); > + if (status & BIT(0)) { > + status &= GENMASK(31, 1); > + writel(status, cmd_q->reg_control + 0x14); > + } > + > + return IRQ_HANDLED; > +} > + > +void ae4_destroy_work(struct ae4_device *ae4) > +{ > + struct ae4_cmd_queue *ae4cmd_q; > + int i; > + > + for (i = 0; i < ae4->cmd_q_count; i++) { > + ae4cmd_q = &ae4->ae4cmd_q[i]; > + > + if (!ae4cmd_q->pws) > + break; > + > + cancel_delayed_work(&ae4cmd_q->p_work); do you need cancel_delayed_work_sync()? > + destroy_workqueue(ae4cmd_q->pws); > + } > +} > + > +int ae4_core_init(struct ae4_device *ae4) > +{ > + struct pt_device *pt = &ae4->pt; > + struct ae4_cmd_queue *ae4cmd_q; > + struct device *dev = pt->dev; > + struct pt_cmd_queue *cmd_q; > + int i, ret = 0; > + > + writel(max_hw_q, pt->io_regs); > + > + for (i = 0; i < max_hw_q; i++) { > + ae4cmd_q = &ae4->ae4cmd_q[i]; > + ae4cmd_q->id = ae4->cmd_q_count; > + ae4->cmd_q_count++; > + > + cmd_q = &ae4cmd_q->cmd_q; > + cmd_q->pt = pt; > + > + /* Preset some register values (Q size is 32byte (0x20)) */ > + cmd_q->reg_control = pt->io_regs + ((i + 1) * 0x20); > + > + ret = devm_request_irq(dev, ae4->ae4_irq[i], ae4_core_irq_handler, 0, > + dev_name(pt->dev), ae4cmd_q); > + if (ret) > + return ret; > + > + cmd_q->qsize = Q_SIZE(sizeof(struct ae4dma_desc)); > + > + cmd_q->qbase = dmam_alloc_coherent(dev, cmd_q->qsize, &cmd_q->qbase_dma, > + GFP_KERNEL); > + if (!cmd_q->qbase) > + return -ENOMEM; > + } > + > + for (i = 0; i < ae4->cmd_q_count; i++) { > + ae4cmd_q = &ae4->ae4cmd_q[i]; > + > + cmd_q = &ae4cmd_q->cmd_q; > + > + /* Preset some register values (Q size is 32byte (0x20)) */ > + cmd_q->reg_control = pt->io_regs + ((i + 1) * 0x20); > + > + /* Update the device registers with queue information. */ > + writel(CMD_Q_LEN, cmd_q->reg_control + 0x08); > + > + cmd_q->qdma_tail = cmd_q->qbase_dma; > + writel(lower_32_bits(cmd_q->qdma_tail), cmd_q->reg_control + 0x18); > + writel(upper_32_bits(cmd_q->qdma_tail), cmd_q->reg_control + 0x1C); > + > + INIT_LIST_HEAD(&ae4cmd_q->cmd); > + init_waitqueue_head(&ae4cmd_q->q_w); > + > + ae4cmd_q->pws = alloc_ordered_workqueue("ae4dma_%d", WQ_MEM_RECLAIM, ae4cmd_q->id); Can existed workqueue match your requirement? Frank > + if (!ae4cmd_q->pws) { > + ae4_destroy_work(ae4); > + return -ENOMEM; > + } > + INIT_DELAYED_WORK(&ae4cmd_q->p_work, ae4_pending_work); > + queue_delayed_work(ae4cmd_q->pws, &ae4cmd_q->p_work, usecs_to_jiffies(100)); > + > + init_completion(&ae4cmd_q->cmp); > + } > + > + return ret; > +} > diff --git a/drivers/dma/amd/ae4dma/ae4dma-pci.c b/drivers/dma/amd/ae4dma/ae4dma-pci.c > new file mode 100644 > index 000000000000..4cd537af757d > --- /dev/null > +++ b/drivers/dma/amd/ae4dma/ae4dma-pci.c > @@ -0,0 +1,195 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * AMD AE4DMA driver > + * > + * Copyright (c) 2024, Advanced Micro Devices, Inc. > + * All Rights Reserved. > + * > + * Author: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > + */ > + > +#include "ae4dma.h" > + > +static int ae4_get_msi_irq(struct ae4_device *ae4) > +{ > + struct pt_device *pt = &ae4->pt; > + struct device *dev = pt->dev; > + struct pci_dev *pdev; > + int ret, i; > + > + pdev = to_pci_dev(dev); > + ret = pci_enable_msi(pdev); > + if (ret) > + return ret; > + > + for (i = 0; i < MAX_AE4_HW_QUEUES; i++) > + ae4->ae4_irq[i] = pdev->irq; > + > + return 0; > +} > + > +static int ae4_get_msix_irqs(struct ae4_device *ae4) > +{ > + struct ae4_msix *ae4_msix = ae4->ae4_msix; > + struct pt_device *pt = &ae4->pt; > + struct device *dev = pt->dev; > + struct pci_dev *pdev; > + int v, i, ret; > + > + pdev = to_pci_dev(dev); > + > + for (v = 0; v < ARRAY_SIZE(ae4_msix->msix_entry); v++) > + ae4_msix->msix_entry[v].entry = v; > + > + ret = pci_enable_msix_range(pdev, ae4_msix->msix_entry, 1, v); > + if (ret < 0) > + return ret; > + > + ae4_msix->msix_count = ret; > + > + for (i = 0; i < MAX_AE4_HW_QUEUES; i++) > + ae4->ae4_irq[i] = ae4_msix->msix_entry[i].vector; > + > + return 0; > +} > + > +static int ae4_get_irqs(struct ae4_device *ae4) > +{ > + struct pt_device *pt = &ae4->pt; > + struct device *dev = pt->dev; > + int ret; > + > + ret = ae4_get_msix_irqs(ae4); > + 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 = ae4_get_msi_irq(ae4); > + if (!ret) > + return 0; > + > + /* Couldn't get MSI interrupt */ > + dev_err(dev, "could not enable MSI (%d)\n", ret); > + > + return ret; > +} > + > +static void ae4_free_irqs(struct ae4_device *ae4) > +{ > + struct ae4_msix *ae4_msix; > + struct pci_dev *pdev; > + struct pt_device *pt; > + struct device *dev; > + int i; > + > + if (ae4) { > + pt = &ae4->pt; > + dev = pt->dev; > + pdev = to_pci_dev(dev); > + > + ae4_msix = ae4->ae4_msix; > + if (ae4_msix && ae4_msix->msix_count) > + pci_disable_msix(pdev); > + else if (pdev->irq) > + pci_disable_msi(pdev); > + > + for (i = 0; i < MAX_AE4_HW_QUEUES; i++) > + ae4->ae4_irq[i] = 0; > + } > +} > + > +static void ae4_deinit(struct ae4_device *ae4) > +{ > + ae4_free_irqs(ae4); > +} > + > +static int ae4_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) > +{ > + struct device *dev = &pdev->dev; > + struct ae4_device *ae4; > + struct pt_device *pt; > + int bar_mask; > + int ret = 0; > + > + ae4 = devm_kzalloc(dev, sizeof(*ae4), GFP_KERNEL); > + if (!ae4) > + return -ENOMEM; > + > + ae4->ae4_msix = devm_kzalloc(dev, sizeof(struct ae4_msix), GFP_KERNEL); > + if (!ae4->ae4_msix) > + return -ENOMEM; > + > + ret = pcim_enable_device(pdev); > + if (ret) > + goto ae4_error; > + > + bar_mask = pci_select_bars(pdev, IORESOURCE_MEM); > + ret = pcim_iomap_regions(pdev, bar_mask, "ae4dma"); > + if (ret) > + goto ae4_error; > + > + pt = &ae4->pt; > + pt->dev = dev; > + > + pt->io_regs = pcim_iomap_table(pdev)[0]; > + if (!pt->io_regs) { > + ret = -ENOMEM; > + goto ae4_error; > + } > + > + ret = ae4_get_irqs(ae4); > + if (ret) > + goto ae4_error; > + > + 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) > + goto ae4_error; > + } needn't failback to 32bit. never return failure when bit >= 32. Detail see: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=f7ae20f2fc4e6a5e32f43c4fa2acab3281a61c81 if (support_48bit) dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48)) else dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)) you decide if support_48bit by hardware register or PID/DID > + > + dev_set_drvdata(dev, ae4); > + > + ret = ae4_core_init(ae4); > + if (ret) > + goto ae4_error; > + > + return 0; > + > +ae4_error: > + ae4_deinit(ae4); > + > + return ret; > +} > + > +static void ae4_pci_remove(struct pci_dev *pdev) > +{ > + struct ae4_device *ae4 = dev_get_drvdata(&pdev->dev); > + > + ae4_destroy_work(ae4); > + ae4_deinit(ae4); > +} > + > +static const struct pci_device_id ae4_pci_table[] = { > + { PCI_VDEVICE(AMD, 0x14C8), }, > + { PCI_VDEVICE(AMD, 0x14DC), }, > + { PCI_VDEVICE(AMD, 0x149B), }, > + /* Last entry must be zero */ > + { 0, } > +}; > +MODULE_DEVICE_TABLE(pci, ae4_pci_table); > + > +static struct pci_driver ae4_pci_driver = { > + .name = "ae4dma", > + .id_table = ae4_pci_table, > + .probe = ae4_pci_probe, > + .remove = ae4_pci_remove, > +}; > + > +module_pci_driver(ae4_pci_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("AMD AE4DMA driver"); > diff --git a/drivers/dma/amd/ae4dma/ae4dma.h b/drivers/dma/amd/ae4dma/ae4dma.h > new file mode 100644 > index 000000000000..24b1253ad570 > --- /dev/null > +++ b/drivers/dma/amd/ae4dma/ae4dma.h > @@ -0,0 +1,77 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * AMD AE4DMA driver > + * > + * Copyright (c) 2024, Advanced Micro Devices, Inc. > + * All Rights Reserved. > + * > + * Author: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > + */ > +#ifndef __AE4DMA_H__ > +#define __AE4DMA_H__ > + > +#include "../common/amd_dma.h" > + > +#define MAX_AE4_HW_QUEUES 16 > + > +#define AE4_DESC_COMPLETED 0x3 > + > +struct ae4_msix { > + int msix_count; > + struct msix_entry msix_entry[MAX_AE4_HW_QUEUES]; > +}; > + > +struct ae4_cmd_queue { > + struct ae4_device *ae4; > + struct pt_cmd_queue cmd_q; > + struct list_head cmd; > + /* protect command operations */ > + struct mutex cmd_lock; > + struct delayed_work p_work; > + struct workqueue_struct *pws; > + struct completion cmp; > + wait_queue_head_t q_w; > + atomic64_t intr_cnt; > + atomic64_t done_cnt; > + atomic64_t q_cmd_count; > + atomic_t dridx; > + unsigned int id; > +}; > + > +union dwou { > + u32 dw0; > + struct dword0 { > + u8 byte0; > + u8 byte1; > + u16 timestamp; > + } dws; > +}; > + > +struct dword1 { > + u8 status; > + u8 err_code; > + u16 desc_id; > +}; > + > +struct ae4dma_desc { > + union dwou dwouv; > + struct dword1 dw1; > + u32 length; > + u32 rsvd; > + u32 src_hi; > + u32 src_lo; > + u32 dst_hi; > + u32 dst_lo; > +}; > + > +struct ae4_device { > + struct pt_device pt; > + struct ae4_msix *ae4_msix; > + struct ae4_cmd_queue ae4cmd_q[MAX_AE4_HW_QUEUES]; > + unsigned int ae4_irq[MAX_AE4_HW_QUEUES]; > + unsigned int cmd_q_count; > +}; > + > +int ae4_core_init(struct ae4_device *ae4); > +void ae4_destroy_work(struct ae4_device *ae4); > +#endif > diff --git a/drivers/dma/amd/common/amd_dma.h b/drivers/dma/amd/common/amd_dma.h > new file mode 100644 > index 000000000000..31c35b3bc94b > --- /dev/null > +++ b/drivers/dma/amd/common/amd_dma.h > @@ -0,0 +1,26 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * AMD DMA Driver common > + * > + * Copyright (c) 2024, Advanced Micro Devices, Inc. > + * All Rights Reserved. > + * > + * Author: Basavaraj Natikar <Basavaraj.Natikar@xxxxxxx> > + */ > + > +#ifndef AMD_DMA_H > +#define AMD_DMA_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> order by alphabet > + > +#include "../ptdma/ptdma.h" > +#include "../../virt-dma.h" > + > +#endif > -- > 2.25.1 >