--- /dev/null
+/*
+ * 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/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.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, 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=%x, dst=%x, len=%d\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 dma_device *dma_dev = &su_dev->shdma_dev.dma_dev;
+ struct shdma_chan *schan;
+ int i;
+
+ shdma_for_each_chan(schan, &su_dev->shdma_dev, i) {
+ struct sudmac_chan *sc = to_chan(schan);
+
+ BUG_ON(!schan);
+
+ shdma_free_irq(&sc->shdma_chan);
+ shdma_chan_remove(schan);
+ }
+ dma_dev->chancnt = 0;
+}
+
+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 = pdev->dev.platform_data;
+ 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;
+
+ chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!chan || !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;
+
+ su_dev->chan_reg = devm_request_and_ioremap(&pdev->dev, chan);
+ if (!su_dev->chan_reg)
+ return err;
+
+ 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 = pdev->dev.platform_data;
+
+ 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);
+
+ platform_set_drvdata(pdev, NULL);
+ 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);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver sudmac_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .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);