diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/dma/fsl-edma.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c new file mode 100644 index 000000000..90bb72af3 --- /dev/null +++ b/drivers/dma/fsl-edma.c @@ -0,0 +1,512 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * drivers/dma/fsl-edma.c + * + * Copyright 2013-2014 Freescale Semiconductor, Inc. + * + * Driver for the Freescale eDMA engine with flexible channel multiplexing + * capability for DMA request sources. The eDMA block can be found on some + * Vybrid and Layerscape SoCs. + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/clk.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 "fsl-edma-common.h" + +static void fsl_edma_synchronize(struct dma_chan *chan) +{ + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan); + + vchan_synchronize(&fsl_chan->vchan); +} + +static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id) +{ + struct fsl_edma_engine *fsl_edma = dev_id; + unsigned int intr, ch; + struct edma_regs *regs = &fsl_edma->regs; + struct fsl_edma_chan *fsl_chan; + + intr = edma_readl(fsl_edma, regs->intl); + if (!intr) + return IRQ_NONE; + + for (ch = 0; ch < fsl_edma->n_chans; ch++) { + if (intr & (0x1 << ch)) { + edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint); + + fsl_chan = &fsl_edma->chans[ch]; + + spin_lock(&fsl_chan->vchan.lock); + + if (!fsl_chan->edesc) { + /* terminate_all called before */ + spin_unlock(&fsl_chan->vchan.lock); + continue; + } + + if (!fsl_chan->edesc->iscyclic) { + list_del(&fsl_chan->edesc->vdesc.node); + vchan_cookie_complete(&fsl_chan->edesc->vdesc); + fsl_chan->edesc = NULL; + fsl_chan->status = DMA_COMPLETE; + fsl_chan->idle = true; + } else { + vchan_cyclic_callback(&fsl_chan->edesc->vdesc); + } + + if (!fsl_chan->edesc) + fsl_edma_xfer_desc(fsl_chan); + + spin_unlock(&fsl_chan->vchan.lock); + } + } + return IRQ_HANDLED; +} + +static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id) +{ + struct fsl_edma_engine *fsl_edma = dev_id; + unsigned int err, ch; + struct edma_regs *regs = &fsl_edma->regs; + + err = edma_readl(fsl_edma, regs->errl); + if (!err) + return IRQ_NONE; + + for (ch = 0; ch < fsl_edma->n_chans; ch++) { + if (err & (0x1 << ch)) { + fsl_edma_disable_request(&fsl_edma->chans[ch]); + edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr); + fsl_edma->chans[ch].status = DMA_ERROR; + fsl_edma->chans[ch].idle = true; + } + } + return IRQ_HANDLED; +} + +static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id) +{ + if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED) + return IRQ_HANDLED; + + return fsl_edma_err_handler(irq, dev_id); +} + +static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data; + struct dma_chan *chan, *_chan; + struct fsl_edma_chan *fsl_chan; + u32 dmamux_nr = fsl_edma->drvdata->dmamuxs; + unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr; + + if (dma_spec->args_count != 2) + return NULL; + + mutex_lock(&fsl_edma->fsl_edma_mutex); + list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) { + if (chan->client_count) + continue; + if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) { + chan = dma_get_slave_channel(chan); + if (chan) { + chan->device->privatecnt++; + fsl_chan = to_fsl_edma_chan(chan); + fsl_chan->slave_id = dma_spec->args[1]; + fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, + true); + mutex_unlock(&fsl_edma->fsl_edma_mutex); + return chan; + } + } + } + mutex_unlock(&fsl_edma->fsl_edma_mutex); + return NULL; +} + +static int +fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma) +{ + int ret; + + fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx"); + if (fsl_edma->txirq < 0) + return fsl_edma->txirq; + + fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err"); + if (fsl_edma->errirq < 0) + return fsl_edma->errirq; + + if (fsl_edma->txirq == fsl_edma->errirq) { + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq, + fsl_edma_irq_handler, 0, "eDMA", fsl_edma); + if (ret) { + dev_err(&pdev->dev, "Can't register eDMA IRQ.\n"); + return ret; + } + } else { + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq, + fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma); + if (ret) { + dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n"); + return ret; + } + + ret = devm_request_irq(&pdev->dev, fsl_edma->errirq, + fsl_edma_err_handler, 0, "eDMA err", fsl_edma); + if (ret) { + dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n"); + return ret; + } + } + + return 0; +} + +static int +fsl_edma2_irq_init(struct platform_device *pdev, + struct fsl_edma_engine *fsl_edma) +{ + int i, ret, irq; + int count; + + count = platform_irq_count(pdev); + dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count); + if (count <= 2) { + dev_err(&pdev->dev, "Interrupts in DTS not correct.\n"); + return -EINVAL; + } + /* + * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp. + * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17... + * For now, just simply request irq without IRQF_SHARED flag, since 16 + * channels are enough on i.mx7ulp whose M4 domain own some peripherals. + */ + for (i = 0; i < count; i++) { + irq = platform_get_irq(pdev, i); + if (irq < 0) + return -ENXIO; + + sprintf(fsl_edma->chans[i].chan_name, "eDMA2-CH%02d", i); + + /* The last IRQ is for eDMA err */ + if (i == count - 1) + ret = devm_request_irq(&pdev->dev, irq, + fsl_edma_err_handler, + 0, "eDMA2-ERR", fsl_edma); + else + ret = devm_request_irq(&pdev->dev, irq, + fsl_edma_tx_handler, 0, + fsl_edma->chans[i].chan_name, + fsl_edma); + if (ret) + return ret; + } + + return 0; +} + +static void fsl_edma_irq_exit( + struct platform_device *pdev, struct fsl_edma_engine *fsl_edma) +{ + if (fsl_edma->txirq == fsl_edma->errirq) { + devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma); + } else { + devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma); + devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma); + } +} + +static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks) +{ + int i; + + for (i = 0; i < nr_clocks; i++) + clk_disable_unprepare(fsl_edma->muxclk[i]); +} + +static struct fsl_edma_drvdata vf610_data = { + .version = v1, + .dmamuxs = DMAMUX_NR, + .setup_irq = fsl_edma_irq_init, +}; + +static struct fsl_edma_drvdata ls1028a_data = { + .version = v1, + .dmamuxs = DMAMUX_NR, + .mux_swap = true, + .setup_irq = fsl_edma_irq_init, +}; + +static struct fsl_edma_drvdata imx7ulp_data = { + .version = v3, + .dmamuxs = 1, + .has_dmaclk = true, + .setup_irq = fsl_edma2_irq_init, +}; + +static const struct of_device_id fsl_edma_dt_ids[] = { + { .compatible = "fsl,vf610-edma", .data = &vf610_data}, + { .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data}, + { .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data}, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids); + +static int fsl_edma_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id = + of_match_device(fsl_edma_dt_ids, &pdev->dev); + struct device_node *np = pdev->dev.of_node; + struct fsl_edma_engine *fsl_edma; + const struct fsl_edma_drvdata *drvdata = NULL; + struct fsl_edma_chan *fsl_chan; + struct edma_regs *regs; + struct resource *res; + int len, chans; + int ret, i; + + if (of_id) + drvdata = of_id->data; + if (!drvdata) { + dev_err(&pdev->dev, "unable to find driver data\n"); + return -EINVAL; + } + + ret = of_property_read_u32(np, "dma-channels", &chans); + if (ret) { + dev_err(&pdev->dev, "Can't get dma-channels.\n"); + return ret; + } + + len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans; + fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL); + if (!fsl_edma) + return -ENOMEM; + + fsl_edma->drvdata = drvdata; + fsl_edma->n_chans = chans; + mutex_init(&fsl_edma->fsl_edma_mutex); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + fsl_edma->membase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(fsl_edma->membase)) + return PTR_ERR(fsl_edma->membase); + + fsl_edma_setup_regs(fsl_edma); + regs = &fsl_edma->regs; + + if (drvdata->has_dmaclk) { + fsl_edma->dmaclk = devm_clk_get(&pdev->dev, "dma"); + if (IS_ERR(fsl_edma->dmaclk)) { + dev_err(&pdev->dev, "Missing DMA block clock.\n"); + return PTR_ERR(fsl_edma->dmaclk); + } + + ret = clk_prepare_enable(fsl_edma->dmaclk); + if (ret) { + dev_err(&pdev->dev, "DMA clk block failed.\n"); + return ret; + } + } + + for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) { + char clkname[32]; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i); + fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(fsl_edma->muxbase[i])) { + /* on error: disable all previously enabled clks */ + fsl_disable_clocks(fsl_edma, i); + return PTR_ERR(fsl_edma->muxbase[i]); + } + + sprintf(clkname, "dmamux%d", i); + fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname); + if (IS_ERR(fsl_edma->muxclk[i])) { + dev_err(&pdev->dev, "Missing DMAMUX block clock.\n"); + /* on error: disable all previously enabled clks */ + fsl_disable_clocks(fsl_edma, i); + return PTR_ERR(fsl_edma->muxclk[i]); + } + + ret = clk_prepare_enable(fsl_edma->muxclk[i]); + if (ret) + /* on error: disable all previously enabled clks */ + fsl_disable_clocks(fsl_edma, i); + + } + + fsl_edma->big_endian = of_property_read_bool(np, "big-endian"); + + INIT_LIST_HEAD(&fsl_edma->dma_dev.channels); + for (i = 0; i < fsl_edma->n_chans; i++) { + struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i]; + + fsl_chan->edma = fsl_edma; + fsl_chan->pm_state = RUNNING; + fsl_chan->slave_id = 0; + fsl_chan->idle = true; + fsl_chan->dma_dir = DMA_NONE; + fsl_chan->vchan.desc_free = fsl_edma_free_desc; + vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev); + + edma_writew(fsl_edma, 0x0, ®s->tcd[i].csr); + fsl_edma_chan_mux(fsl_chan, 0, false); + } + + edma_writel(fsl_edma, ~0, regs->intl); + ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma); + if (ret) + return ret; + + dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask); + dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask); + dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask); + + fsl_edma->dma_dev.dev = &pdev->dev; + fsl_edma->dma_dev.device_alloc_chan_resources + = fsl_edma_alloc_chan_resources; + fsl_edma->dma_dev.device_free_chan_resources + = fsl_edma_free_chan_resources; + fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status; + fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg; + fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic; + fsl_edma->dma_dev.device_config = fsl_edma_slave_config; + fsl_edma->dma_dev.device_pause = fsl_edma_pause; + fsl_edma->dma_dev.device_resume = fsl_edma_resume; + fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all; + fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize; + fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending; + + fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS; + fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS; + fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + + platform_set_drvdata(pdev, fsl_edma); + + ret = dma_async_device_register(&fsl_edma->dma_dev); + if (ret) { + dev_err(&pdev->dev, + "Can't register Freescale eDMA engine. (%d)\n", ret); + fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs); + return ret; + } + + ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma); + if (ret) { + dev_err(&pdev->dev, + "Can't register Freescale eDMA of_dma. (%d)\n", ret); + dma_async_device_unregister(&fsl_edma->dma_dev); + fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs); + return ret; + } + + /* enable round robin arbitration */ + edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr); + + return 0; +} + +static int fsl_edma_remove(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev); + + fsl_edma_irq_exit(pdev, fsl_edma); + fsl_edma_cleanup_vchan(&fsl_edma->dma_dev); + of_dma_controller_free(np); + dma_async_device_unregister(&fsl_edma->dma_dev); + fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs); + + return 0; +} + +static int fsl_edma_suspend_late(struct device *dev) +{ + struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev); + struct fsl_edma_chan *fsl_chan; + unsigned long flags; + int i; + + for (i = 0; i < fsl_edma->n_chans; i++) { + fsl_chan = &fsl_edma->chans[i]; + spin_lock_irqsave(&fsl_chan->vchan.lock, flags); + /* Make sure chan is idle or will force disable. */ + if (unlikely(!fsl_chan->idle)) { + dev_warn(dev, "WARN: There is non-idle channel."); + fsl_edma_disable_request(fsl_chan); + fsl_edma_chan_mux(fsl_chan, 0, false); + } + + fsl_chan->pm_state = SUSPENDED; + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags); + } + + return 0; +} + +static int fsl_edma_resume_early(struct device *dev) +{ + struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev); + struct fsl_edma_chan *fsl_chan; + struct edma_regs *regs = &fsl_edma->regs; + int i; + + for (i = 0; i < fsl_edma->n_chans; i++) { + fsl_chan = &fsl_edma->chans[i]; + fsl_chan->pm_state = RUNNING; + edma_writew(fsl_edma, 0x0, ®s->tcd[i].csr); + if (fsl_chan->slave_id != 0) + fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true); + } + + edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr); + + return 0; +} + +/* + * eDMA provides the service to others, so it should be suspend late + * and resume early. When eDMA suspend, all of the clients should stop + * the DMA data transmission and let the channel idle. + */ +static const struct dev_pm_ops fsl_edma_pm_ops = { + .suspend_late = fsl_edma_suspend_late, + .resume_early = fsl_edma_resume_early, +}; + +static struct platform_driver fsl_edma_driver = { + .driver = { + .name = "fsl-edma", + .of_match_table = fsl_edma_dt_ids, + .pm = &fsl_edma_pm_ops, + }, + .probe = fsl_edma_probe, + .remove = fsl_edma_remove, +}; + +static int __init fsl_edma_init(void) +{ + return platform_driver_register(&fsl_edma_driver); +} +subsys_initcall(fsl_edma_init); + +static void __exit fsl_edma_exit(void) +{ + platform_driver_unregister(&fsl_edma_driver); +} +module_exit(fsl_edma_exit); + +MODULE_ALIAS("platform:fsl-edma"); +MODULE_DESCRIPTION("Freescale eDMA engine driver"); +MODULE_LICENSE("GPL v2"); |