diff options
Diffstat (limited to 'drivers/dma/sh/sudmac.c')
-rw-r--r-- | drivers/dma/sh/sudmac.c | 422 |
1 files changed, 422 insertions, 0 deletions
diff --git a/drivers/dma/sh/sudmac.c b/drivers/dma/sh/sudmac.c new file mode 100644 index 000000000..6da2eaa6c --- /dev/null +++ b/drivers/dma/sh/sudmac.c @@ -0,0 +1,422 @@ +/* + * Renesas SUDMAC support + * + * Copyright (C) 2013 Renesas Solutions Corp. + * + * based on drivers/dma/sh/shdma.c: + * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com> + * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved. + * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved. + * + * This is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ + +#include <linux/dmaengine.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/sudmac.h> + +struct sudmac_chan { + struct shdma_chan shdma_chan; + void __iomem *base; + char dev_id[16]; /* unique name per DMAC of channel */ + + u32 offset; /* for CFG, BA, BBC, CA, CBC, DEN */ + u32 cfg; + u32 dint_end_bit; +}; + +struct sudmac_device { + struct shdma_dev shdma_dev; + struct sudmac_pdata *pdata; + void __iomem *chan_reg; +}; + +struct sudmac_regs { + u32 base_addr; + u32 base_byte_count; +}; + +struct sudmac_desc { + struct sudmac_regs hw; + struct shdma_desc shdma_desc; +}; + +#define to_chan(schan) container_of(schan, struct sudmac_chan, shdma_chan) +#define to_desc(sdesc) container_of(sdesc, struct sudmac_desc, shdma_desc) +#define to_sdev(sc) container_of(sc->shdma_chan.dma_chan.device, \ + struct sudmac_device, shdma_dev.dma_dev) + +/* SUDMAC register */ +#define SUDMAC_CH0CFG 0x00 +#define SUDMAC_CH0BA 0x10 +#define SUDMAC_CH0BBC 0x18 +#define SUDMAC_CH0CA 0x20 +#define SUDMAC_CH0CBC 0x28 +#define SUDMAC_CH0DEN 0x30 +#define SUDMAC_DSTSCLR 0x38 +#define SUDMAC_DBUFCTRL 0x3C +#define SUDMAC_DINTCTRL 0x40 +#define SUDMAC_DINTSTS 0x44 +#define SUDMAC_DINTSTSCLR 0x48 +#define SUDMAC_CH0SHCTRL 0x50 + +/* Definitions for the sudmac_channel.config */ +#define SUDMAC_SENDBUFM 0x1000 /* b12: Transmit Buffer Mode */ +#define SUDMAC_RCVENDM 0x0100 /* b8: Receive Data Transfer End Mode */ +#define SUDMAC_LBA_WAIT 0x0030 /* b5-4: Local Bus Access Wait */ + +/* Definitions for the sudmac_channel.dint_end_bit */ +#define SUDMAC_CH1ENDE 0x0002 /* b1: Ch1 DMA Transfer End Int Enable */ +#define SUDMAC_CH0ENDE 0x0001 /* b0: Ch0 DMA Transfer End Int Enable */ + +#define SUDMAC_DRV_NAME "sudmac" + +static void sudmac_writel(struct sudmac_chan *sc, u32 data, u32 reg) +{ + iowrite32(data, sc->base + reg); +} + +static u32 sudmac_readl(struct sudmac_chan *sc, u32 reg) +{ + return ioread32(sc->base + reg); +} + +static bool sudmac_is_busy(struct sudmac_chan *sc) +{ + u32 den = sudmac_readl(sc, SUDMAC_CH0DEN + sc->offset); + + if (den) + return true; /* working */ + + return false; /* waiting */ +} + +static void sudmac_set_reg(struct sudmac_chan *sc, struct sudmac_regs *hw, + struct shdma_desc *sdesc) +{ + sudmac_writel(sc, sc->cfg, SUDMAC_CH0CFG + sc->offset); + sudmac_writel(sc, hw->base_addr, SUDMAC_CH0BA + sc->offset); + sudmac_writel(sc, hw->base_byte_count, SUDMAC_CH0BBC + sc->offset); +} + +static void sudmac_start(struct sudmac_chan *sc) +{ + u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL); + + sudmac_writel(sc, dintctrl | sc->dint_end_bit, SUDMAC_DINTCTRL); + sudmac_writel(sc, 1, SUDMAC_CH0DEN + sc->offset); +} + +static void sudmac_start_xfer(struct shdma_chan *schan, + struct shdma_desc *sdesc) +{ + struct sudmac_chan *sc = to_chan(schan); + struct sudmac_desc *sd = to_desc(sdesc); + + sudmac_set_reg(sc, &sd->hw, sdesc); + sudmac_start(sc); +} + +static bool sudmac_channel_busy(struct shdma_chan *schan) +{ + struct sudmac_chan *sc = to_chan(schan); + + return sudmac_is_busy(sc); +} + +static void sudmac_setup_xfer(struct shdma_chan *schan, int slave_id) +{ +} + +static const struct sudmac_slave_config *sudmac_find_slave( + struct sudmac_chan *sc, int slave_id) +{ + struct sudmac_device *sdev = to_sdev(sc); + struct sudmac_pdata *pdata = sdev->pdata; + const struct sudmac_slave_config *cfg; + int i; + + for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++) + if (cfg->slave_id == slave_id) + return cfg; + + return NULL; +} + +static int sudmac_set_slave(struct shdma_chan *schan, int slave_id, + dma_addr_t slave_addr, bool try) +{ + struct sudmac_chan *sc = to_chan(schan); + const struct sudmac_slave_config *cfg = sudmac_find_slave(sc, slave_id); + + if (!cfg) + return -ENODEV; + + return 0; +} + +static inline void sudmac_dma_halt(struct sudmac_chan *sc) +{ + u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL); + + sudmac_writel(sc, 0, SUDMAC_CH0DEN + sc->offset); + sudmac_writel(sc, dintctrl & ~sc->dint_end_bit, SUDMAC_DINTCTRL); + sudmac_writel(sc, sc->dint_end_bit, SUDMAC_DINTSTSCLR); +} + +static int sudmac_desc_setup(struct shdma_chan *schan, + struct shdma_desc *sdesc, + dma_addr_t src, dma_addr_t dst, size_t *len) +{ + struct sudmac_chan *sc = to_chan(schan); + struct sudmac_desc *sd = to_desc(sdesc); + + dev_dbg(sc->shdma_chan.dev, "%s: src=%pad, dst=%pad, len=%zu\n", + __func__, &src, &dst, *len); + + if (*len > schan->max_xfer_len) + *len = schan->max_xfer_len; + + if (dst) + sd->hw.base_addr = dst; + else if (src) + sd->hw.base_addr = src; + sd->hw.base_byte_count = *len; + + return 0; +} + +static void sudmac_halt(struct shdma_chan *schan) +{ + struct sudmac_chan *sc = to_chan(schan); + + sudmac_dma_halt(sc); +} + +static bool sudmac_chan_irq(struct shdma_chan *schan, int irq) +{ + struct sudmac_chan *sc = to_chan(schan); + u32 dintsts = sudmac_readl(sc, SUDMAC_DINTSTS); + + if (!(dintsts & sc->dint_end_bit)) + return false; + + /* DMA stop */ + sudmac_dma_halt(sc); + + return true; +} + +static size_t sudmac_get_partial(struct shdma_chan *schan, + struct shdma_desc *sdesc) +{ + struct sudmac_chan *sc = to_chan(schan); + struct sudmac_desc *sd = to_desc(sdesc); + u32 current_byte_count = sudmac_readl(sc, SUDMAC_CH0CBC + sc->offset); + + return sd->hw.base_byte_count - current_byte_count; +} + +static bool sudmac_desc_completed(struct shdma_chan *schan, + struct shdma_desc *sdesc) +{ + struct sudmac_chan *sc = to_chan(schan); + struct sudmac_desc *sd = to_desc(sdesc); + u32 current_addr = sudmac_readl(sc, SUDMAC_CH0CA + sc->offset); + + return sd->hw.base_addr + sd->hw.base_byte_count == current_addr; +} + +static int sudmac_chan_probe(struct sudmac_device *su_dev, int id, int irq, + unsigned long flags) +{ + struct shdma_dev *sdev = &su_dev->shdma_dev; + struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev); + struct sudmac_chan *sc; + struct shdma_chan *schan; + int err; + + sc = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_chan), GFP_KERNEL); + if (!sc) { + dev_err(sdev->dma_dev.dev, + "No free memory for allocating dma channels!\n"); + return -ENOMEM; + } + + schan = &sc->shdma_chan; + schan->max_xfer_len = 64 * 1024 * 1024 - 1; + + shdma_chan_probe(sdev, schan, id); + + sc->base = su_dev->chan_reg; + + /* get platform_data */ + sc->offset = su_dev->pdata->channel->offset; + if (su_dev->pdata->channel->config & SUDMAC_TX_BUFFER_MODE) + sc->cfg |= SUDMAC_SENDBUFM; + if (su_dev->pdata->channel->config & SUDMAC_RX_END_MODE) + sc->cfg |= SUDMAC_RCVENDM; + sc->cfg |= (su_dev->pdata->channel->wait << 4) & SUDMAC_LBA_WAIT; + + if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH0) + sc->dint_end_bit |= SUDMAC_CH0ENDE; + if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH1) + sc->dint_end_bit |= SUDMAC_CH1ENDE; + + /* set up channel irq */ + if (pdev->id >= 0) + snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d.%d", + pdev->id, id); + else + snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d", id); + + err = shdma_request_irq(schan, irq, flags, sc->dev_id); + if (err) { + dev_err(sdev->dma_dev.dev, + "DMA channel %d request_irq failed %d\n", id, err); + goto err_no_irq; + } + + return 0; + +err_no_irq: + /* remove from dmaengine device node */ + shdma_chan_remove(schan); + return err; +} + +static void sudmac_chan_remove(struct sudmac_device *su_dev) +{ + struct shdma_chan *schan; + int i; + + shdma_for_each_chan(schan, &su_dev->shdma_dev, i) { + BUG_ON(!schan); + + shdma_chan_remove(schan); + } +} + +static dma_addr_t sudmac_slave_addr(struct shdma_chan *schan) +{ + /* SUDMAC doesn't need the address */ + return 0; +} + +static struct shdma_desc *sudmac_embedded_desc(void *buf, int i) +{ + return &((struct sudmac_desc *)buf)[i].shdma_desc; +} + +static const struct shdma_ops sudmac_shdma_ops = { + .desc_completed = sudmac_desc_completed, + .halt_channel = sudmac_halt, + .channel_busy = sudmac_channel_busy, + .slave_addr = sudmac_slave_addr, + .desc_setup = sudmac_desc_setup, + .set_slave = sudmac_set_slave, + .setup_xfer = sudmac_setup_xfer, + .start_xfer = sudmac_start_xfer, + .embedded_desc = sudmac_embedded_desc, + .chan_irq = sudmac_chan_irq, + .get_partial = sudmac_get_partial, +}; + +static int sudmac_probe(struct platform_device *pdev) +{ + struct sudmac_pdata *pdata = dev_get_platdata(&pdev->dev); + int err, i; + struct sudmac_device *su_dev; + struct dma_device *dma_dev; + struct resource *chan, *irq_res; + + /* get platform data */ + if (!pdata) + return -ENODEV; + + irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!irq_res) + return -ENODEV; + + err = -ENOMEM; + su_dev = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_device), + GFP_KERNEL); + if (!su_dev) { + dev_err(&pdev->dev, "Not enough memory\n"); + return err; + } + + dma_dev = &su_dev->shdma_dev.dma_dev; + + chan = platform_get_resource(pdev, IORESOURCE_MEM, 0); + su_dev->chan_reg = devm_ioremap_resource(&pdev->dev, chan); + if (IS_ERR(su_dev->chan_reg)) + return PTR_ERR(su_dev->chan_reg); + + dma_cap_set(DMA_SLAVE, dma_dev->cap_mask); + + su_dev->shdma_dev.ops = &sudmac_shdma_ops; + su_dev->shdma_dev.desc_size = sizeof(struct sudmac_desc); + err = shdma_init(&pdev->dev, &su_dev->shdma_dev, pdata->channel_num); + if (err < 0) + return err; + + /* platform data */ + su_dev->pdata = dev_get_platdata(&pdev->dev); + + platform_set_drvdata(pdev, su_dev); + + /* Create DMA Channel */ + for (i = 0; i < pdata->channel_num; i++) { + err = sudmac_chan_probe(su_dev, i, irq_res->start, IRQF_SHARED); + if (err) + goto chan_probe_err; + } + + err = dma_async_device_register(&su_dev->shdma_dev.dma_dev); + if (err < 0) + goto chan_probe_err; + + return err; + +chan_probe_err: + sudmac_chan_remove(su_dev); + + shdma_cleanup(&su_dev->shdma_dev); + + return err; +} + +static int sudmac_remove(struct platform_device *pdev) +{ + struct sudmac_device *su_dev = platform_get_drvdata(pdev); + struct dma_device *dma_dev = &su_dev->shdma_dev.dma_dev; + + dma_async_device_unregister(dma_dev); + sudmac_chan_remove(su_dev); + shdma_cleanup(&su_dev->shdma_dev); + + return 0; +} + +static struct platform_driver sudmac_driver = { + .driver = { + .name = SUDMAC_DRV_NAME, + }, + .probe = sudmac_probe, + .remove = sudmac_remove, +}; +module_platform_driver(sudmac_driver); + +MODULE_AUTHOR("Yoshihiro Shimoda"); +MODULE_DESCRIPTION("Renesas SUDMAC driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" SUDMAC_DRV_NAME); |