diff options
Diffstat (limited to 'drivers/dma/milbeaut-hdmac.c')
| -rw-r--r-- | drivers/dma/milbeaut-hdmac.c | 578 |
1 files changed, 578 insertions, 0 deletions
diff --git a/drivers/dma/milbeaut-hdmac.c b/drivers/dma/milbeaut-hdmac.c new file mode 100644 index 000000000..1b0a95892 --- /dev/null +++ b/drivers/dma/milbeaut-hdmac.c @@ -0,0 +1,578 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (C) 2019 Linaro Ltd. +// Copyright (C) 2019 Socionext Inc. + +#include <linux/bits.h> +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/bitfield.h> + +#include "virt-dma.h" + +#define MLB_HDMAC_DMACR 0x0 /* global */ +#define MLB_HDMAC_DE BIT(31) +#define MLB_HDMAC_DS BIT(30) +#define MLB_HDMAC_PR BIT(28) +#define MLB_HDMAC_DH GENMASK(27, 24) + +#define MLB_HDMAC_CH_STRIDE 0x10 + +#define MLB_HDMAC_DMACA 0x0 /* channel */ +#define MLB_HDMAC_EB BIT(31) +#define MLB_HDMAC_PB BIT(30) +#define MLB_HDMAC_ST BIT(29) +#define MLB_HDMAC_IS GENMASK(28, 24) +#define MLB_HDMAC_BT GENMASK(23, 20) +#define MLB_HDMAC_BC GENMASK(19, 16) +#define MLB_HDMAC_TC GENMASK(15, 0) +#define MLB_HDMAC_DMACB 0x4 +#define MLB_HDMAC_TT GENMASK(31, 30) +#define MLB_HDMAC_MS GENMASK(29, 28) +#define MLB_HDMAC_TW GENMASK(27, 26) +#define MLB_HDMAC_FS BIT(25) +#define MLB_HDMAC_FD BIT(24) +#define MLB_HDMAC_RC BIT(23) +#define MLB_HDMAC_RS BIT(22) +#define MLB_HDMAC_RD BIT(21) +#define MLB_HDMAC_EI BIT(20) +#define MLB_HDMAC_CI BIT(19) +#define HDMAC_PAUSE 0x7 +#define MLB_HDMAC_SS GENMASK(18, 16) +#define MLB_HDMAC_SP GENMASK(15, 12) +#define MLB_HDMAC_DP GENMASK(11, 8) +#define MLB_HDMAC_DMACSA 0x8 +#define MLB_HDMAC_DMACDA 0xc + +#define MLB_HDMAC_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) + +struct milbeaut_hdmac_desc { + struct virt_dma_desc vd; + struct scatterlist *sgl; + unsigned int sg_len; + unsigned int sg_cur; + enum dma_transfer_direction dir; +}; + +struct milbeaut_hdmac_chan { + struct virt_dma_chan vc; + struct milbeaut_hdmac_device *mdev; + struct milbeaut_hdmac_desc *md; + void __iomem *reg_ch_base; + unsigned int slave_id; + struct dma_slave_config cfg; +}; + +struct milbeaut_hdmac_device { + struct dma_device ddev; + struct clk *clk; + void __iomem *reg_base; + struct milbeaut_hdmac_chan channels[]; +}; + +static struct milbeaut_hdmac_chan * +to_milbeaut_hdmac_chan(struct virt_dma_chan *vc) +{ + return container_of(vc, struct milbeaut_hdmac_chan, vc); +} + +static struct milbeaut_hdmac_desc * +to_milbeaut_hdmac_desc(struct virt_dma_desc *vd) +{ + return container_of(vd, struct milbeaut_hdmac_desc, vd); +} + +/* mc->vc.lock must be held by caller */ +static struct milbeaut_hdmac_desc * +milbeaut_hdmac_next_desc(struct milbeaut_hdmac_chan *mc) +{ + struct virt_dma_desc *vd; + + vd = vchan_next_desc(&mc->vc); + if (!vd) { + mc->md = NULL; + return NULL; + } + + list_del(&vd->node); + + mc->md = to_milbeaut_hdmac_desc(vd); + + return mc->md; +} + +/* mc->vc.lock must be held by caller */ +static void milbeaut_chan_start(struct milbeaut_hdmac_chan *mc, + struct milbeaut_hdmac_desc *md) +{ + struct scatterlist *sg; + u32 cb, ca, src_addr, dest_addr, len; + u32 width, burst; + + sg = &md->sgl[md->sg_cur]; + len = sg_dma_len(sg); + + cb = MLB_HDMAC_CI | MLB_HDMAC_EI; + if (md->dir == DMA_MEM_TO_DEV) { + cb |= MLB_HDMAC_FD; + width = mc->cfg.dst_addr_width; + burst = mc->cfg.dst_maxburst; + src_addr = sg_dma_address(sg); + dest_addr = mc->cfg.dst_addr; + } else { + cb |= MLB_HDMAC_FS; + width = mc->cfg.src_addr_width; + burst = mc->cfg.src_maxburst; + src_addr = mc->cfg.src_addr; + dest_addr = sg_dma_address(sg); + } + cb |= FIELD_PREP(MLB_HDMAC_TW, (width >> 1)); + cb |= FIELD_PREP(MLB_HDMAC_MS, 2); + + writel_relaxed(MLB_HDMAC_DE, mc->mdev->reg_base + MLB_HDMAC_DMACR); + writel_relaxed(src_addr, mc->reg_ch_base + MLB_HDMAC_DMACSA); + writel_relaxed(dest_addr, mc->reg_ch_base + MLB_HDMAC_DMACDA); + writel_relaxed(cb, mc->reg_ch_base + MLB_HDMAC_DMACB); + + ca = FIELD_PREP(MLB_HDMAC_IS, mc->slave_id); + if (burst == 16) + ca |= FIELD_PREP(MLB_HDMAC_BT, 0xf); + else if (burst == 8) + ca |= FIELD_PREP(MLB_HDMAC_BT, 0xd); + else if (burst == 4) + ca |= FIELD_PREP(MLB_HDMAC_BT, 0xb); + burst *= width; + ca |= FIELD_PREP(MLB_HDMAC_TC, (len / burst - 1)); + writel_relaxed(ca, mc->reg_ch_base + MLB_HDMAC_DMACA); + ca |= MLB_HDMAC_EB; + writel_relaxed(ca, mc->reg_ch_base + MLB_HDMAC_DMACA); +} + +/* mc->vc.lock must be held by caller */ +static void milbeaut_hdmac_start(struct milbeaut_hdmac_chan *mc) +{ + struct milbeaut_hdmac_desc *md; + + md = milbeaut_hdmac_next_desc(mc); + if (md) + milbeaut_chan_start(mc, md); +} + +static irqreturn_t milbeaut_hdmac_interrupt(int irq, void *dev_id) +{ + struct milbeaut_hdmac_chan *mc = dev_id; + struct milbeaut_hdmac_desc *md; + u32 val; + + spin_lock(&mc->vc.lock); + + /* Ack and Disable irqs */ + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACB); + val &= ~(FIELD_PREP(MLB_HDMAC_SS, HDMAC_PAUSE)); + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACB); + val &= ~MLB_HDMAC_EI; + val &= ~MLB_HDMAC_CI; + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACB); + + md = mc->md; + if (!md) + goto out; + + md->sg_cur++; + + if (md->sg_cur >= md->sg_len) { + vchan_cookie_complete(&md->vd); + md = milbeaut_hdmac_next_desc(mc); + if (!md) + goto out; + } + + milbeaut_chan_start(mc, md); + +out: + spin_unlock(&mc->vc.lock); + return IRQ_HANDLED; +} + +static void milbeaut_hdmac_free_chan_resources(struct dma_chan *chan) +{ + vchan_free_chan_resources(to_virt_chan(chan)); +} + +static int +milbeaut_hdmac_chan_config(struct dma_chan *chan, struct dma_slave_config *cfg) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); + + spin_lock(&mc->vc.lock); + mc->cfg = *cfg; + spin_unlock(&mc->vc.lock); + + return 0; +} + +static int milbeaut_hdmac_chan_pause(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); + u32 val; + + spin_lock(&mc->vc.lock); + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACA); + val |= MLB_HDMAC_PB; + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACA); + spin_unlock(&mc->vc.lock); + + return 0; +} + +static int milbeaut_hdmac_chan_resume(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); + u32 val; + + spin_lock(&mc->vc.lock); + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACA); + val &= ~MLB_HDMAC_PB; + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACA); + spin_unlock(&mc->vc.lock); + + return 0; +} + +static struct dma_async_tx_descriptor * +milbeaut_hdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, + enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_desc *md; + int i; + + if (!is_slave_direction(direction)) + return NULL; + + md = kzalloc(sizeof(*md), GFP_NOWAIT); + if (!md) + return NULL; + + md->sgl = kcalloc(sg_len, sizeof(*sgl), GFP_NOWAIT); + if (!md->sgl) { + kfree(md); + return NULL; + } + + for (i = 0; i < sg_len; i++) + md->sgl[i] = sgl[i]; + + md->sg_len = sg_len; + md->dir = direction; + + return vchan_tx_prep(vc, &md->vd, flags); +} + +static int milbeaut_hdmac_terminate_all(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); + unsigned long flags; + u32 val; + + LIST_HEAD(head); + + spin_lock_irqsave(&vc->lock, flags); + + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACA); + val &= ~MLB_HDMAC_EB; /* disable the channel */ + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACA); + + if (mc->md) { + vchan_terminate_vdesc(&mc->md->vd); + mc->md = NULL; + } + + vchan_get_all_descriptors(vc, &head); + + spin_unlock_irqrestore(&vc->lock, flags); + + vchan_dma_desc_free_list(vc, &head); + + return 0; +} + +static void milbeaut_hdmac_synchronize(struct dma_chan *chan) +{ + vchan_synchronize(to_virt_chan(chan)); +} + +static enum dma_status milbeaut_hdmac_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct virt_dma_chan *vc; + struct virt_dma_desc *vd; + struct milbeaut_hdmac_chan *mc; + struct milbeaut_hdmac_desc *md = NULL; + enum dma_status stat; + unsigned long flags; + int i; + + stat = dma_cookie_status(chan, cookie, txstate); + /* Return immediately if we do not need to compute the residue. */ + if (stat == DMA_COMPLETE || !txstate) + return stat; + + vc = to_virt_chan(chan); + + spin_lock_irqsave(&vc->lock, flags); + + mc = to_milbeaut_hdmac_chan(vc); + + /* residue from the on-flight chunk */ + if (mc->md && mc->md->vd.tx.cookie == cookie) { + struct scatterlist *sg; + u32 done; + + md = mc->md; + sg = &md->sgl[md->sg_cur]; + + if (md->dir == DMA_DEV_TO_MEM) + done = readl_relaxed(mc->reg_ch_base + + MLB_HDMAC_DMACDA); + else + done = readl_relaxed(mc->reg_ch_base + + MLB_HDMAC_DMACSA); + done -= sg_dma_address(sg); + + txstate->residue = -done; + } + + if (!md) { + vd = vchan_find_desc(vc, cookie); + if (vd) + md = to_milbeaut_hdmac_desc(vd); + } + + if (md) { + /* residue from the queued chunks */ + for (i = md->sg_cur; i < md->sg_len; i++) + txstate->residue += sg_dma_len(&md->sgl[i]); + } + + spin_unlock_irqrestore(&vc->lock, flags); + + return stat; +} + +static void milbeaut_hdmac_issue_pending(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); + unsigned long flags; + + spin_lock_irqsave(&vc->lock, flags); + + if (vchan_issue_pending(vc) && !mc->md) + milbeaut_hdmac_start(mc); + + spin_unlock_irqrestore(&vc->lock, flags); +} + +static void milbeaut_hdmac_desc_free(struct virt_dma_desc *vd) +{ + struct milbeaut_hdmac_desc *md = to_milbeaut_hdmac_desc(vd); + + kfree(md->sgl); + kfree(md); +} + +static struct dma_chan * +milbeaut_hdmac_xlate(struct of_phandle_args *dma_spec, struct of_dma *of_dma) +{ + struct milbeaut_hdmac_device *mdev = of_dma->of_dma_data; + struct milbeaut_hdmac_chan *mc; + struct virt_dma_chan *vc; + struct dma_chan *chan; + + if (dma_spec->args_count != 1) + return NULL; + + chan = dma_get_any_slave_channel(&mdev->ddev); + if (!chan) + return NULL; + + vc = to_virt_chan(chan); + mc = to_milbeaut_hdmac_chan(vc); + mc->slave_id = dma_spec->args[0]; + + return chan; +} + +static int milbeaut_hdmac_chan_init(struct platform_device *pdev, + struct milbeaut_hdmac_device *mdev, + int chan_id) +{ + struct device *dev = &pdev->dev; + struct milbeaut_hdmac_chan *mc = &mdev->channels[chan_id]; + char *irq_name; + int irq, ret; + + irq = platform_get_irq(pdev, chan_id); + if (irq < 0) + return irq; + + irq_name = devm_kasprintf(dev, GFP_KERNEL, "milbeaut-hdmac-%d", + chan_id); + if (!irq_name) + return -ENOMEM; + + ret = devm_request_irq(dev, irq, milbeaut_hdmac_interrupt, + IRQF_SHARED, irq_name, mc); + if (ret) + return ret; + + mc->mdev = mdev; + mc->reg_ch_base = mdev->reg_base + MLB_HDMAC_CH_STRIDE * (chan_id + 1); + mc->vc.desc_free = milbeaut_hdmac_desc_free; + vchan_init(&mc->vc, &mdev->ddev); + + return 0; +} + +static int milbeaut_hdmac_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct milbeaut_hdmac_device *mdev; + struct dma_device *ddev; + int nr_chans, ret, i; + + nr_chans = platform_irq_count(pdev); + if (nr_chans < 0) + return nr_chans; + + ret = dma_set_mask(dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + + mdev = devm_kzalloc(dev, struct_size(mdev, channels, nr_chans), + GFP_KERNEL); + if (!mdev) + return -ENOMEM; + + mdev->reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mdev->reg_base)) + return PTR_ERR(mdev->reg_base); + + mdev->clk = devm_clk_get(dev, NULL); + if (IS_ERR(mdev->clk)) { + dev_err(dev, "failed to get clock\n"); + return PTR_ERR(mdev->clk); + } + + ret = clk_prepare_enable(mdev->clk); + if (ret) + return ret; + + ddev = &mdev->ddev; + ddev->dev = dev; + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + dma_cap_set(DMA_PRIVATE, ddev->cap_mask); + ddev->src_addr_widths = MLB_HDMAC_BUSWIDTHS; + ddev->dst_addr_widths = MLB_HDMAC_BUSWIDTHS; + ddev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM); + ddev->device_free_chan_resources = milbeaut_hdmac_free_chan_resources; + ddev->device_config = milbeaut_hdmac_chan_config; + ddev->device_pause = milbeaut_hdmac_chan_pause; + ddev->device_resume = milbeaut_hdmac_chan_resume; + ddev->device_prep_slave_sg = milbeaut_hdmac_prep_slave_sg; + ddev->device_terminate_all = milbeaut_hdmac_terminate_all; + ddev->device_synchronize = milbeaut_hdmac_synchronize; + ddev->device_tx_status = milbeaut_hdmac_tx_status; + ddev->device_issue_pending = milbeaut_hdmac_issue_pending; + INIT_LIST_HEAD(&ddev->channels); + + for (i = 0; i < nr_chans; i++) { + ret = milbeaut_hdmac_chan_init(pdev, mdev, i); + if (ret) + goto disable_clk; + } + + ret = dma_async_device_register(ddev); + if (ret) + goto disable_clk; + + ret = of_dma_controller_register(dev->of_node, + milbeaut_hdmac_xlate, mdev); + if (ret) + goto unregister_dmac; + + platform_set_drvdata(pdev, mdev); + + return 0; + +unregister_dmac: + dma_async_device_unregister(ddev); +disable_clk: + clk_disable_unprepare(mdev->clk); + + return ret; +} + +static int milbeaut_hdmac_remove(struct platform_device *pdev) +{ + struct milbeaut_hdmac_device *mdev = platform_get_drvdata(pdev); + struct dma_chan *chan; + int ret; + + /* + * Before reaching here, almost all descriptors have been freed by the + * ->device_free_chan_resources() hook. However, each channel might + * be still holding one descriptor that was on-flight at that moment. + * Terminate it to make sure this hardware is no longer running. Then, + * free the channel resources once again to avoid memory leak. + */ + list_for_each_entry(chan, &mdev->ddev.channels, device_node) { + ret = dmaengine_terminate_sync(chan); + if (ret) + return ret; + milbeaut_hdmac_free_chan_resources(chan); + } + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&mdev->ddev); + clk_disable_unprepare(mdev->clk); + + return 0; +} + +static const struct of_device_id milbeaut_hdmac_match[] = { + { .compatible = "socionext,milbeaut-m10v-hdmac" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, milbeaut_hdmac_match); + +static struct platform_driver milbeaut_hdmac_driver = { + .probe = milbeaut_hdmac_probe, + .remove = milbeaut_hdmac_remove, + .driver = { + .name = "milbeaut-m10v-hdmac", + .of_match_table = milbeaut_hdmac_match, + }, +}; +module_platform_driver(milbeaut_hdmac_driver); + +MODULE_DESCRIPTION("Milbeaut HDMAC DmaEngine driver"); +MODULE_LICENSE("GPL v2"); |