Link: https://www.kernel.org/doc/html/v4.17/driver-api/dmaengine/ Link: https://static.dev.sifive.com/FU540-C000-v1.0.pdf
Add PDMA driver, sf-pdma, to enable DMA engine on HiFive Unleashed Rev A00 board. - Implement dmaengine APIs, support MEM_TO_MEM async copy. - Tested by DMA Test client - Supports 4 channels DMA, each channel has 1 done and 1 err interrupt connected to platform-level interrupt controller (PLIC). - Depends on DMA_ENGINE and DMA_VIRTUAL_CHANNELS Follow the DMAengine controller doc, "./Documentation/driver-api/dmaengine/provider.rst" to implement DMA engine. And use the dma test client in doc, "./Documentation/driver-api/dmaengine/dmatest.rst", to test. Each DMA channel has separate HW regs and support done and error ISRs. 4 channels share 1 done and 1 err ISRs. There's no expander/arbitrator in DMA HW. ------ ------ | |--< done 23 >--|ch 0| | |--< err 24 >--| | (dma0chan0) | | ------ | | ------ | |--< done 25 >--|ch 1| | |--< err 26 >--| | (dma0chan1) |PLIC| ------ | | ------ | |--< done 27 >--|ch 2| | |--< err 28 >--| | (dma0chan2) | | ------ | | ------ | |--< done 29 >--|ch 3| | |--< err 30 >--| | (dma0chan3) ------ ------ Signed-off-by: Green Wan <green....@sifive.com> --- MAINTAINERS | 1 + drivers/dma/Kconfig | 2 + drivers/dma/Makefile | 1 + drivers/dma/sf-pdma/Kconfig | 6 + drivers/dma/sf-pdma/Makefile | 1 + drivers/dma/sf-pdma/sf-pdma.c | 609 ++++++++++++++++++++++++++++++++++ drivers/dma/sf-pdma/sf-pdma.h | 124 +++++++ 7 files changed, 744 insertions(+) create mode 100644 drivers/dma/sf-pdma/Kconfig create mode 100644 drivers/dma/sf-pdma/Makefile create mode 100644 drivers/dma/sf-pdma/sf-pdma.c create mode 100644 drivers/dma/sf-pdma/sf-pdma.h diff --git a/MAINTAINERS b/MAINTAINERS index d0caa09a479e..c5f0662c9106 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14594,6 +14594,7 @@ F: drivers/media/mmc/siano/ SIFIVE PDMA DRIVER M: Green Wan <green....@sifive.com> S: Maintained +F: drivers/dma/sf-pdma/ F: Documentation/devicetree/bindings/dma/sifive,fu540-c000-pdma.yaml SIFIVE DRIVERS diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 413efef5fbb6..f05a928f5a3d 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -667,6 +667,8 @@ source "drivers/dma/qcom/Kconfig" source "drivers/dma/dw/Kconfig" +source "drivers/dma/sf-pdma/Kconfig" + source "drivers/dma/dw-edma/Kconfig" source "drivers/dma/hsu/Kconfig" diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 5bddf6f8790f..77a552d970ae 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_DMA_SUN4I) += sun4i-dma.o obj-$(CONFIG_DMA_SUN6I) += sun6i-dma.o obj-$(CONFIG_DW_AXI_DMAC) += dw-axi-dmac/ obj-$(CONFIG_DW_DMAC_CORE) += dw/ +obj-$(CONFIG_SF_PDMA) += sf-pdma/ obj-$(CONFIG_DW_EDMA) += dw-edma/ obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o obj-$(CONFIG_FSL_DMA) += fsldma.o diff --git a/drivers/dma/sf-pdma/Kconfig b/drivers/dma/sf-pdma/Kconfig new file mode 100644 index 000000000000..0e01a5728a79 --- /dev/null +++ b/drivers/dma/sf-pdma/Kconfig @@ -0,0 +1,6 @@ +config SF_PDMA + bool "Sifive PDMA controller driver" + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Support the SiFive PDMA controller. diff --git a/drivers/dma/sf-pdma/Makefile b/drivers/dma/sf-pdma/Makefile new file mode 100644 index 000000000000..764552ab8d0a --- /dev/null +++ b/drivers/dma/sf-pdma/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_SF_PDMA) += sf-pdma.o diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c new file mode 100644 index 000000000000..ecea0cf17d40 --- /dev/null +++ b/drivers/dma/sf-pdma/sf-pdma.c @@ -0,0 +1,609 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/** + * SiFive FU540 Platform DMA driver + * Copyright (C) 2019 SiFive + * + * Based partially on: + * - drivers/dma/fsl-edma.c + * - drivers/dma/dw-edma/ + * - drivers/dma/pxa-dma.c + * + * See the following sources for further documentation: + * - Chapter 12 "Platform DMA Engine (PDMA)" of + * SiFive FU540-C000 v1.0 + * https://static.dev.sifive.com/FU540-C000-v1.0.pdf + */ +#include <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/pm_runtime.h> +#include <linux/dmaengine.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/dma-mapping.h> +#include <linux/irq.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_dma.h> +#include <linux/time64.h> + +#include "sf-pdma.h" +#include "../dmaengine.h" +#include "../virt-dma.h" + +#define SIFIVE_PDMA_NAME "sf-pdma" + +static inline struct sf_pdma_chan *to_sf_pdma_chan(struct dma_chan *dchan) +{ + return container_of(dchan, struct sf_pdma_chan, vchan.chan); +} + +static inline struct sf_pdma_desc *to_sf_pdma_desc(struct virt_dma_desc *vd) +{ + return container_of(vd, struct sf_pdma_desc, vdesc); +} + +static struct sf_pdma_desc *sf_pdma_alloc_desc(struct sf_pdma_chan *chan) +{ + struct sf_pdma_desc *desc; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + + if (chan->desc && !chan->desc->in_use) { + spin_unlock_irqrestore(&chan->lock, flags); + return chan->desc; + } + + spin_unlock_irqrestore(&chan->lock, flags); + + desc = kzalloc(sizeof(*desc), GFP_NOWAIT); + + if (!desc) + return NULL; + + desc->chan = chan; + + return desc; +} + +static void sf_pdma_fill_desc(struct sf_pdma_chan *chan, + u64 dst, + u64 src, + u64 size) +{ + struct pdma_regs *regs = &chan->regs; + + writel(PDMA_FULL_SPEED, regs->xfer_type); + writeq(size, regs->xfer_size); + writeq(dst, regs->dst_addr); + writeq(src, regs->src_addr); +} + +void sf_pdma_disclaim_chan(struct sf_pdma_chan *chan) +{ + struct pdma_regs *regs = &chan->regs; + + writel(PDMA_CLEAR_CTRL, regs->ctrl); +} + +struct dma_async_tx_descriptor * + sf_pdma_prep_dma_memcpy(struct dma_chan *dchan, + dma_addr_t dest, + dma_addr_t src, + size_t len, + unsigned long flags) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + struct sf_pdma_desc *desc; + + if (!chan || !len || !dest || !src) { + pr_debug("%s: Please check dma len, dest, src!\n", __func__); + return NULL; + } + + desc = sf_pdma_alloc_desc(chan); + if (!desc) + return NULL; + + desc->in_use = true; + desc->dirn = DMA_MEM_TO_MEM; + desc->async_tx = vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); + + spin_lock_irqsave(&chan->lock, flags); + chan->desc = desc; + sf_pdma_fill_desc(desc->chan, dest, src, len); + spin_unlock_irqrestore(&chan->lock, flags); + + return desc->async_tx; +} + +static void sf_pdma_unprep_slave_dma(struct sf_pdma_chan *chan) +{ + if (chan->dma_dir != DMA_NONE) + dma_unmap_resource(chan->vchan.chan.device->dev, + chan->dma_dev_addr, + chan->dma_dev_size, + chan->dma_dir, 0); + chan->dma_dir = DMA_NONE; +} + +static int sf_pdma_slave_config(struct dma_chan *dchan, + struct dma_slave_config *cfg) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + + memcpy(&chan->cfg, cfg, sizeof(*cfg)); + sf_pdma_unprep_slave_dma(chan); + + return 0; +} + +static int sf_pdma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + struct pdma_regs *regs = &chan->regs; + + dma_cookie_init(dchan); + writel(PDMA_CLAIM_MASK, regs->ctrl); + + return 0; +} + +static void sf_pdma_disable_request(struct sf_pdma_chan *chan) +{ + struct pdma_regs *regs = &chan->regs; + + writel(readl(regs->ctrl) & ~PDMA_RUN_MASK, regs->ctrl); +} + +static void sf_pdma_free_chan_resources(struct dma_chan *dchan) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&chan->vchan.lock, flags); + sf_pdma_disable_request(chan); + kfree(chan->desc); + chan->desc = NULL; + vchan_get_all_descriptors(&chan->vchan, &head); + sf_pdma_unprep_slave_dma(chan); + vchan_dma_desc_free_list(&chan->vchan, &head); + sf_pdma_disclaim_chan(chan); + spin_unlock_irqrestore(&chan->vchan.lock, flags); +} + +static size_t sf_pdma_desc_residue(struct sf_pdma_chan *chan, + dma_cookie_t cookie) +{ + struct virt_dma_desc *vd = NULL; + struct sf_pdma_desc *desc; + struct pdma_regs *regs = &chan->regs; + unsigned long flags; + u64 residue; + + residue = readq(regs->residue); + + chan->status = residue ? DMA_IN_PROGRESS : DMA_COMPLETE; + + spin_lock_irqsave(&chan->vchan.lock, flags); + vd = vchan_find_desc(&chan->vchan, cookie); + if (!vd) + goto out; + + desc = to_sf_pdma_desc(vd); + + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + if (desc && chan->status == DMA_COMPLETE) + vchan_tx_desc_free(desc->async_tx); + + return residue; + +out: + spin_unlock_irqrestore(&chan->vchan.lock, flags); + return residue; +} + +static enum dma_status +sf_pdma_tx_status(struct dma_chan *dchan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + enum dma_status status; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + if (chan->xfer_err) { + chan->status = DMA_ERROR; + spin_unlock_irqrestore(&chan->lock, flags); + return chan->status; + } + + spin_unlock_irqrestore(&chan->lock, flags); + + status = dma_cookie_status(dchan, cookie, txstate); + + if (status == DMA_COMPLETE) + return status; + + if (!txstate) + return chan->status; + + txstate->residue = sf_pdma_desc_residue(chan, cookie); + + return chan->status; +} + +static int sf_pdma_terminate_all(struct dma_chan *dchan) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&chan->vchan.lock, flags); + sf_pdma_disable_request(chan); + kfree(chan->desc); + chan->desc = NULL; + chan->xfer_err = false; + vchan_get_all_descriptors(&chan->vchan, &head); + vchan_dma_desc_free_list(&chan->vchan, &head); + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + return 0; +} + +static void sf_pdma_enable_request(struct sf_pdma_chan *chan) +{ + struct pdma_regs *regs = &chan->regs; + u32 v; + + v = PDMA_CLAIM_MASK | + PDMA_ENABLE_DONE_INT_MASK | + PDMA_ENABLE_ERR_INT_MASK | + PDMA_RUN_MASK; + + writel(v, regs->ctrl); +} + +static void sf_pdma_xfer_desc(struct sf_pdma_chan *chan) +{ + struct virt_dma_desc *vdesc; + + vdesc = vchan_next_desc(&chan->vchan); + if (!vdesc) + return; + + chan->desc = to_sf_pdma_desc(vdesc); + chan->status = DMA_IN_PROGRESS; +} + +static void sf_pdma_issue_pending(struct dma_chan *dchan) +{ + struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan); + unsigned long flags; + + spin_lock_irqsave(&chan->vchan.lock, flags); + + if (chan->pm_state != RUNNING) { + spin_unlock_irqrestore(&chan->vchan.lock, flags); + /* cannot submit due to suspend */ + return; + } + + if (vchan_issue_pending(&chan->vchan) && !chan->desc) + sf_pdma_xfer_desc(chan); + + sf_pdma_enable_request(chan); + spin_unlock_irqrestore(&chan->vchan.lock, flags); +} + +static void sf_pdma_free_desc(struct virt_dma_desc *vdesc) +{ + struct sf_pdma_desc *desc; + unsigned long flags; + + desc = to_sf_pdma_desc(vdesc); + desc->in_use = false; +} + +static void sf_pdma_donebh_tasklet(unsigned long arg) +{ + struct sf_pdma_chan *chan = (struct sf_pdma_chan *)arg; + struct sf_pdma_desc *desc = chan->desc; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + if (chan->xfer_err) { + chan->retries = MAX_RETRY; + chan->status = DMA_COMPLETE; + chan->xfer_err = false; + } + spin_unlock_irqrestore(&chan->lock, flags); + + dmaengine_desc_get_callback_invoke(desc->async_tx, NULL); +} + +static void sf_pdma_errbh_tasklet(unsigned long arg) +{ + struct sf_pdma_chan *chan = (struct sf_pdma_chan *)arg; + struct sf_pdma_desc *desc = chan->desc; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + if (chan->retries <= 0) { + /* fail to recover, tx_status() is in DMA_ERROR */ + spin_unlock_irqrestore(&chan->lock, flags); + dmaengine_desc_get_callback_invoke(desc->async_tx, NULL); + } else { + /* retry */ + chan->retries--; + chan->xfer_err = true; + chan->status = DMA_ERROR; + + sf_pdma_enable_request(chan); + spin_unlock_irqrestore(&chan->lock, flags); + } +} + +static irqreturn_t sf_pdma_done_isr(int irq, void *dev_id) +{ + struct sf_pdma_chan *chan = dev_id; + struct pdma_regs *regs = &chan->regs; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + writel((readl(regs->ctrl)) & ~PDMA_DONE_STATUS_MASK, regs->ctrl); + spin_unlock_irqrestore(&chan->lock, flags); + + tasklet_hi_schedule(&chan->done_tasklet); + + return IRQ_HANDLED; +} + +static irqreturn_t sf_pdma_err_isr(int irq, void *dev_id) +{ + struct sf_pdma_chan *chan = dev_id; + struct pdma_regs *regs = &chan->regs; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + writel((readl(regs->ctrl)) & ~PDMA_ERR_STATUS_MASK, regs->ctrl); + spin_unlock_irqrestore(&chan->lock, flags); + + tasklet_schedule(&chan->err_tasklet); + + return IRQ_HANDLED; +} + +/** + * sf_pdma_irq_init() - Init PDMA IRQ Handlers + * @pdev: pointer of platform_device + * @pdma: pointer of PDMA engine. Caller should check NULL + * + * Initialize DONE and ERROR interrupt handler for 4 channels. Caller should + * make sure the pointer passed in are non-NULL. This function should be called + * only one time during the device probe. + * + * Context: Any context. + * + * Return: + * * 0 - OK to init all IRQ handlers + * * irq - Fail to retrieve from DT binding + * * -1 - Fail to call request_irq() + */ +static int sf_pdma_irq_init(struct platform_device *pdev, struct sf_pdma *pdma) +{ + int irq, r, i; + struct sf_pdma_chan *chan; + + for (i = 0; i < pdma->n_chans; i++) { + chan = &pdma->chans[i]; + + irq = platform_get_irq(pdev, i * 2); + if (irq < 0) { + dev_err(&pdev->dev, "Can't get pdma done irq.\n"); + return irq; + } + + r = request_irq(irq, sf_pdma_done_isr, 0, + dev_name(&pdev->dev), (void *)chan); + if (r) { + dev_err(&pdev->dev, "Fail to attach done ISR: %d\n", r); + return -1; + } + + chan->txirq = irq; + + irq = platform_get_irq(pdev, (i * 2) + 1); + if (irq < 0) { + dev_err(&pdev->dev, "Can't get pdma err irq.\n"); + return irq; + } + + r = request_irq(irq, sf_pdma_err_isr, 0, + dev_name(&pdev->dev), (void *)chan); + if (r) { + dev_err(&pdev->dev, "Fail to attach err ISR: %d\n", r); + return -1; + } + + chan->errirq = irq; + } + + return 0; +} + +/** + * sf_pdma_setup_chans() - Init settings of each channel + * @pdma: pointer of PDMA engine. Caller should check NULL + * + * Initialize all data structure and register base. Caller should make sure + * the pointer passed in are non-NULL. This function should be called only + * one time during the device probe. + * + * Context: Any context. + * + * Return: none + */ +#define SF_PDMA_REG_BASE(ch) (pdma->membase + (PDMA_CHAN_OFFSET * (ch))) +static void sf_pdma_setup_chans(struct sf_pdma *pdma) +{ + int i; + struct sf_pdma_chan *chan; + + INIT_LIST_HEAD(&pdma->dma_dev.channels); + + for (i = 0; i < pdma->n_chans; i++) { + chan = &pdma->chans[i]; + + chan->regs.ctrl = + SF_PDMA_REG_BASE(i) + PDMA_CTRL; + chan->regs.xfer_type = + SF_PDMA_REG_BASE(i) + PDMA_XFER_TYPE; + chan->regs.xfer_size = + SF_PDMA_REG_BASE(i) + PDMA_XFER_SIZE; + chan->regs.dst_addr = + SF_PDMA_REG_BASE(i) + PDMA_DST_ADDR; + chan->regs.src_addr = + SF_PDMA_REG_BASE(i) + PDMA_SRC_ADDR; + chan->regs.act_type = + SF_PDMA_REG_BASE(i) + PDMA_ACT_TYPE; + chan->regs.residue = + SF_PDMA_REG_BASE(i) + PDMA_REMAINING_BYTE; + chan->regs.cur_dst_addr = + SF_PDMA_REG_BASE(i) + PDMA_CUR_DST_ADDR; + chan->regs.cur_src_addr = + SF_PDMA_REG_BASE(i) + PDMA_CUR_SRC_ADDR; + + chan->pdma = pdma; + chan->pm_state = RUNNING; + chan->slave_id = i; + chan->xfer_err = false; + spin_lock_init(&chan->lock); + + chan->vchan.desc_free = sf_pdma_free_desc; + vchan_init(&chan->vchan, &pdma->dma_dev); + + writel(PDMA_CLEAR_CTRL, chan->regs.ctrl); + + tasklet_init(&chan->done_tasklet, + sf_pdma_donebh_tasklet, (unsigned long)chan); + tasklet_init(&chan->err_tasklet, + sf_pdma_errbh_tasklet, (unsigned long)chan); + } +} + +static int sf_pdma_probe(struct platform_device *pdev) +{ + struct sf_pdma *pdma; + struct sf_pdma_chan *chan; + struct resource *res; + int len, chans; + int ret; + + chans = PDMA_NR_CH; + len = sizeof(*pdma) + sizeof(*chan) * chans; + pdma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL); + if (!pdma) + return -ENOMEM; + + pdma->n_chans = chans; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pdma->membase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pdma->membase)) + goto ERR_MEMBASE; + + ret = sf_pdma_irq_init(pdev, pdma); + if (ret) + goto ERR_INITIRQ; + + sf_pdma_setup_chans(pdma); + + pdma->dma_dev.dev = &pdev->dev; + dma_cap_set(DMA_MEMCPY, pdma->dma_dev.cap_mask); + + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (ret) + pr_warn("*** Failed to set DMA mask. Fall back to default.\n"); + + /* Setup DMA APIs */ + pdma->dma_dev.device_alloc_chan_resources = + sf_pdma_alloc_chan_resources; + pdma->dma_dev.device_free_chan_resources = + sf_pdma_free_chan_resources; + pdma->dma_dev.device_tx_status = sf_pdma_tx_status; + pdma->dma_dev.device_prep_dma_memcpy = sf_pdma_prep_dma_memcpy; + pdma->dma_dev.device_config = sf_pdma_slave_config; + pdma->dma_dev.device_terminate_all = sf_pdma_terminate_all; + pdma->dma_dev.device_issue_pending = sf_pdma_issue_pending; + + platform_set_drvdata(pdev, pdma); + + ret = dma_async_device_register(&pdma->dma_dev); + if (ret) + goto ERR_REG_DMADEVICE; + + return 0; + +ERR_MEMBASE: + devm_kfree(&pdev->dev, pdma); + return PTR_ERR(pdma->membase); + +ERR_INITIRQ: + devm_kfree(&pdev->dev, pdma); + return ret; + +ERR_REG_DMADEVICE: + devm_kfree(&pdev->dev, pdma); + dev_err(&pdev->dev, + "Can't register SiFive Platform DMA. (%d)\n", ret); + return ret; +} + +static int sf_pdma_remove(struct platform_device *pdev) +{ + struct sf_pdma *pdma = platform_get_drvdata(pdev); + + dma_async_device_unregister(&pdma->dma_dev); + + return 0; +} + +static const struct of_device_id sf_pdma_of_match[] = { + { .compatible = "sifive,fu540-c000-pdma" }, + {}, +}; +MODULE_DEVICE_TABLE(of, sifive_serial_of_match); + +static struct platform_driver sf_pdma_driver = { + .probe = sf_pdma_probe, + .remove = sf_pdma_remove, + .driver = { + .name = SIFIVE_PDMA_NAME, + .of_match_table = of_match_ptr(sf_pdma_of_match), + }, +}; + +static int __init sf_pdma_init(void) +{ + return platform_driver_register(&sf_pdma_driver); +} + +static void __exit sf_pdma_exit(void) +{ + platform_driver_unregister(&sf_pdma_driver); +} + +/* do early init */ +subsys_initcall(sf_pdma_init); +module_exit(sf_pdma_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("SiFive Platform DMA driver"); +MODULE_AUTHOR("Green Wan <green....@sifive.com>"); diff --git a/drivers/dma/sf-pdma/sf-pdma.h b/drivers/dma/sf-pdma/sf-pdma.h new file mode 100644 index 000000000000..d577d5af0bf4 --- /dev/null +++ b/drivers/dma/sf-pdma/sf-pdma.h @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/** + * SiFive FU540 Platform DMA driver + * Copyright (C) 2019 SiFive + * + * Based partially on: + * - drivers/dma/fsl-edma.c + * - drivers/dma/dw-edma/ + * - drivers/dma/pxa-dma.c + * + * See the following sources for further documentation: + * - Chapter 12 "Platform DMA Engine (PDMA)" of + * SiFive FU540-C000 v1.0 + * https://static.dev.sifive.com/FU540-C000-v1.0.pdf + */ +#ifndef _SF_PDMA_H +#define _SF_PDMA_H + +#include <linux/msi.h> +#include <linux/dmaengine.h> +#include <linux/dma-direction.h> +#include <linux/timer.h> +#include <linux/time64.h> +#include <linux/timekeeping.h> +#include <linux/workqueue.h> + +#include "../dmaengine.h" +#include "../virt-dma.h" + +#define PDMA_NR_CH 4 + +#if (PDMA_NR_CH != 4) +#error "Please define PDMA_NR_CH to 4" +#endif + +#define PDMA_BASE_ADDR 0x3000000 +#define PDMA_CHAN_OFFSET 0x1000 + +/* Register Offset */ +#define PDMA_CTRL 0x000 +#define PDMA_XFER_TYPE 0x004 +#define PDMA_XFER_SIZE 0x008 +#define PDMA_DST_ADDR 0x010 +#define PDMA_SRC_ADDR 0x018 +#define PDMA_ACT_TYPE 0x104 /* Read-only */ +#define PDMA_REMAINING_BYTE 0x108 /* Read-only */ +#define PDMA_CUR_DST_ADDR 0x110 /* Read-only*/ +#define PDMA_CUR_SRC_ADDR 0x118 /* Read-only*/ + +/* CTRL */ +#define PDMA_CLEAR_CTRL 0x0 +#define PDMA_CLAIM_MASK GENMASK(0, 0) +#define PDMA_RUN_MASK GENMASK(1, 1) +#define PDMA_ENABLE_DONE_INT_MASK GENMASK(14, 14) +#define PDMA_ENABLE_ERR_INT_MASK GENMASK(15, 15) +#define PDMA_DONE_STATUS_MASK GENMASK(30, 30) +#define PDMA_ERR_STATUS_MASK GENMASK(31, 31) + +/* Transfer Type */ +#define PDMA_FULL_SPEED 0xFF000008 + +/* Error Recovery */ +#define MAX_RETRY 1 + +struct pdma_regs { + /* read-write regs */ + void __iomem *ctrl; /* 4 bytes */ + + void __iomem *xfer_type; /* 4 bytes */ + void __iomem *xfer_size; /* 8 bytes */ + void __iomem *dst_addr; /* 8 bytes */ + void __iomem *src_addr; /* 8 bytes */ + + /* read-only */ + void __iomem *act_type; /* 4 bytes */ + void __iomem *residue; /* 8 bytes */ + void __iomem *cur_dst_addr; /* 8 bytes */ + void __iomem *cur_src_addr; /* 8 bytes */ +}; + +struct sf_pdma_desc { + struct virt_dma_desc vdesc; + struct sf_pdma_chan *chan; + bool in_use; + enum dma_transfer_direction dirn; + struct dma_async_tx_descriptor *async_tx; +}; + +enum sf_pdma_pm_state { + RUNNING = 0, + SUSPENDED, +}; + +struct sf_pdma_chan { + struct virt_dma_chan vchan; + enum dma_status status; + enum sf_pdma_pm_state pm_state; + u32 slave_id; + struct sf_pdma *pdma; + struct sf_pdma_desc *desc; + struct dma_slave_config cfg; + u32 attr; + dma_addr_t dma_dev_addr; + u32 dma_dev_size; + enum dma_data_direction dma_dir; + struct tasklet_struct done_tasklet; + struct tasklet_struct err_tasklet; + struct pdma_regs regs; + spinlock_t lock; /* protect chan data */ + bool xfer_err; + int txirq; + int errirq; + int retries; +}; + +struct sf_pdma { + struct dma_device dma_dev; + void __iomem *membase; + void __iomem *mappedbase; + u32 n_chans; + struct sf_pdma_chan chans[PDMA_NR_CH]; +}; + +#endif /* _SF_PDMA_H */ -- 2.17.1
