1 files changed, 722 insertions, 0 deletions

diff --git a/arch/arm/plat-s3c64xx/dma.c b/arch/arm/plat-s3c64xx/dma.c
new file mode 100644
index 00000000000..67aa93dbb69
--- /dev/null
+++ b/arch/arm/plat-s3c64xx/dma.c
@@ -0,0 +1,722 @@
+/* linux/arch/arm/plat-s3c64xx/dma.c
+ *
+ * Copyright 2009 Openmoko, Inc.
+ * Copyright 2009 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>
+ *	http://armlinux.simtec.co.uk/
+ *
+ * S3C64XX DMA core
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/dmapool.h>
+#include <linux/sysdev.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+
+#include <mach/dma.h>
+#include <mach/map.h>
+#include <mach/irqs.h>
+
+#include <plat/dma-plat.h>
+#include <plat/regs-sys.h>
+
+#include <asm/hardware/pl080.h>
+
+/* dma channel state information */
+
+struct s3c64xx_dmac {
+	struct sys_device	 sysdev;
+	struct clk		*clk;
+	void __iomem		*regs;
+	struct s3c2410_dma_chan *channels;
+	enum dma_ch		 chanbase;
+};
+
+/* pool to provide LLI buffers */
+static struct dma_pool *dma_pool;
+
+/* Debug configuration and code */
+
+static unsigned char debug_show_buffs = 0;
+
+static void dbg_showchan(struct s3c2410_dma_chan *chan)
+{
+	pr_debug("DMA%d: %08x->%08x L %08x C %08x,%08x S %08x\n",
+		 chan->number,
+		 readl(chan->regs + PL080_CH_SRC_ADDR),
+		 readl(chan->regs + PL080_CH_DST_ADDR),
+		 readl(chan->regs + PL080_CH_LLI),
+		 readl(chan->regs + PL080_CH_CONTROL),
+		 readl(chan->regs + PL080S_CH_CONTROL2),
+		 readl(chan->regs + PL080S_CH_CONFIG));
+}
+
+static void show_lli(struct pl080s_lli *lli)
+{
+	pr_debug("LLI[%p] %08x->%08x, NL %08x C %08x,%08x\n",
+		 lli, lli->src_addr, lli->dst_addr, lli->next_lli,
+		 lli->control0, lli->control1);
+}
+
+static void dbg_showbuffs(struct s3c2410_dma_chan *chan)
+{
+	struct s3c64xx_dma_buff *ptr;
+	struct s3c64xx_dma_buff *end;
+
+	pr_debug("DMA%d: buffs next %p, curr %p, end %p\n",
+		 chan->number, chan->next, chan->curr, chan->end);
+
+	ptr = chan->next;
+	end = chan->end;
+
+	if (debug_show_buffs) {
+		for (; ptr != NULL; ptr = ptr->next) {
+			pr_debug("DMA%d: %08x ",
+				 chan->number, ptr->lli_dma);
+			show_lli(ptr->lli);
+		}
+	}
+}
+
+/* End of Debug */
+
+static struct s3c2410_dma_chan *s3c64xx_dma_map_channel(unsigned int channel)
+{
+	struct s3c2410_dma_chan *chan;
+	unsigned int start, offs;
+
+	start = 0;
+
+	if (channel >= DMACH_PCM1_TX)
+		start = 8;
+
+	for (offs = 0; offs < 8; offs++) {
+		chan = &s3c2410_chans[start + offs];
+		if (!chan->in_use)
+			goto found;
+	}
+
+	return NULL;
+
+found:
+	s3c_dma_chan_map[channel] = chan;
+	return chan;
+}
+
+int s3c2410_dma_config(unsigned int channel, int xferunit)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+
+	if (chan == NULL)
+		return -EINVAL;
+
+	switch (xferunit) {
+	case 1:
+		chan->hw_width = 0;
+		break;
+	case 2:
+		chan->hw_width = 1;
+		break;
+	case 4:
+		chan->hw_width = 2;
+		break;
+	default:
+		printk(KERN_ERR "%s: illegal width %d\n", __func__, xferunit);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(s3c2410_dma_config);
+
+static void s3c64xx_dma_fill_lli(struct s3c2410_dma_chan *chan,
+				 struct pl080s_lli *lli,
+				 dma_addr_t data, int size)
+{
+	dma_addr_t src, dst;
+	u32 control0, control1;
+
+	switch (chan->source) {
+	case S3C2410_DMASRC_HW:
+		src = chan->dev_addr;
+		dst = data;
+		control0 = PL080_CONTROL_SRC_AHB2;
+		control0 |= (u32)chan->hw_width << PL080_CONTROL_SWIDTH_SHIFT;
+		control0 |= 2 << PL080_CONTROL_DWIDTH_SHIFT;
+		control0 |= PL080_CONTROL_DST_INCR;
+		break;
+
+	case S3C2410_DMASRC_MEM:
+		src = data;
+		dst = chan->dev_addr;
+		control0 = PL080_CONTROL_DST_AHB2;
+		control0 |= (u32)chan->hw_width << PL080_CONTROL_DWIDTH_SHIFT;
+		control0 |= 2 << PL080_CONTROL_SWIDTH_SHIFT;
+		control0 |= PL080_CONTROL_SRC_INCR;
+		break;
+	default:
+		BUG();
+	}
+
+	/* note, we do not currently setup any of the burst controls */
+
+	control1 = size >> chan->hw_width;	/* size in no of xfers */
+	control0 |= PL080_CONTROL_PROT_SYS;	/* always in priv. mode */
+	control0 |= PL080_CONTROL_TC_IRQ_EN;	/* always fire IRQ */
+
+	lli->src_addr = src;
+	lli->dst_addr = dst;
+	lli->next_lli = 0;
+	lli->control0 = control0;
+	lli->control1 = control1;
+}
+
+static void s3c64xx_lli_to_regs(struct s3c2410_dma_chan *chan,
+				struct pl080s_lli *lli)
+{
+	void __iomem *regs = chan->regs;
+
+	pr_debug("%s: LLI %p => regs\n", __func__, lli);
+	show_lli(lli);
+
+	writel(lli->src_addr, regs + PL080_CH_SRC_ADDR);
+	writel(lli->dst_addr, regs + PL080_CH_DST_ADDR);
+	writel(lli->next_lli, regs + PL080_CH_LLI);
+	writel(lli->control0, regs + PL080_CH_CONTROL);
+	writel(lli->control1, regs + PL080S_CH_CONTROL2);
+}
+
+static int s3c64xx_dma_start(struct s3c2410_dma_chan *chan)
+{
+	struct s3c64xx_dmac *dmac = chan->dmac;
+	u32 config;
+	u32 bit = chan->bit;
+
+	dbg_showchan(chan);
+
+	pr_debug("%s: clearing interrupts\n", __func__);
+
+	/* clear interrupts */
+	writel(bit, dmac->regs + PL080_TC_CLEAR);
+	writel(bit, dmac->regs + PL080_ERR_CLEAR);
+
+	pr_debug("%s: starting channel\n", __func__);
+
+	config = readl(chan->regs + PL080S_CH_CONFIG);
+	config |= PL080_CONFIG_ENABLE;
+
+	pr_debug("%s: writing config %08x\n", __func__, config);
+	writel(config, chan->regs + PL080S_CH_CONFIG);
+
+	return 0;
+}
+
+static int s3c64xx_dma_stop(struct s3c2410_dma_chan *chan)
+{
+	u32 config;
+	int timeout;
+
+	pr_debug("%s: stopping channel\n", __func__);
+
+	dbg_showchan(chan);
+
+	config = readl(chan->regs + PL080S_CH_CONFIG);
+	config |= PL080_CONFIG_HALT;
+	writel(config, chan->regs + PL080S_CH_CONFIG);
+
+	timeout = 1000;
+	do {
+		config = readl(chan->regs + PL080S_CH_CONFIG);
+		pr_debug("%s: %d - config %08x\n", __func__, timeout, config);
+		if (config & PL080_CONFIG_ACTIVE)
+			udelay(10);
+		else
+			break;
+		} while (--timeout > 0);
+
+	if (config & PL080_CONFIG_ACTIVE) {
+		printk(KERN_ERR "%s: channel still active\n", __func__);
+		return -EFAULT;
+	}
+
+	config = readl(chan->regs + PL080S_CH_CONFIG);
+	config &= ~PL080_CONFIG_ENABLE;
+	writel(config, chan->regs + PL080S_CH_CONFIG);
+
+	return 0;
+}
+
+static inline void s3c64xx_dma_bufffdone(struct s3c2410_dma_chan *chan,
+					 struct s3c64xx_dma_buff *buf,
+					 enum s3c2410_dma_buffresult result)
+{
+	if (chan->callback_fn != NULL)
+		(chan->callback_fn)(chan, buf->pw, 0, result);
+}
+
+static void s3c64xx_dma_freebuff(struct s3c64xx_dma_buff *buff)
+{
+	dma_pool_free(dma_pool, buff->lli, buff->lli_dma);
+	kfree(buff);
+}
+
+static int s3c64xx_dma_flush(struct s3c2410_dma_chan *chan)
+{
+	struct s3c64xx_dma_buff *buff, *next;
+	u32 config;
+
+	dbg_showchan(chan);
+
+	pr_debug("%s: flushing channel\n", __func__);
+
+	config = readl(chan->regs + PL080S_CH_CONFIG);
+	config &= ~PL080_CONFIG_ENABLE;
+	writel(config, chan->regs + PL080S_CH_CONFIG);
+
+	/* dump all the buffers associated with this channel */
+
+	for (buff = chan->curr; buff != NULL; buff = next) {
+		next = buff->next;
+		pr_debug("%s: buff %p (next %p)\n", __func__, buff, buff->next);
+
+		s3c64xx_dma_bufffdone(chan, buff, S3C2410_RES_ABORT);
+		s3c64xx_dma_freebuff(buff);
+	}
+
+	chan->curr = chan->next = chan->end = NULL;
+
+	return 0;
+}
+
+int s3c2410_dma_ctrl(unsigned int channel, enum s3c2410_chan_op op)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+
+	WARN_ON(!chan);
+	if (!chan)
+		return -EINVAL;
+
+	switch (op) {
+	case S3C2410_DMAOP_START:
+		return s3c64xx_dma_start(chan);
+
+	case S3C2410_DMAOP_STOP:
+		return s3c64xx_dma_stop(chan);
+
+	case S3C2410_DMAOP_FLUSH:
+		return s3c64xx_dma_flush(chan);
+
+	/* belive PAUSE/RESUME are no-ops */
+	case S3C2410_DMAOP_PAUSE:
+	case S3C2410_DMAOP_RESUME:
+	case S3C2410_DMAOP_STARTED:
+	case S3C2410_DMAOP_TIMEOUT:
+		return 0;
+	}
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL(s3c2410_dma_ctrl);
+
+/* s3c2410_dma_enque
+ *
+ */
+
+int s3c2410_dma_enqueue(unsigned int channel, void *id,
+			dma_addr_t data, int size)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+	struct s3c64xx_dma_buff *next;
+	struct s3c64xx_dma_buff *buff;
+	struct pl080s_lli *lli;
+	int ret;
+
+	WARN_ON(!chan);
+	if (!chan)
+		return -EINVAL;
+
+	buff = kzalloc(sizeof(struct s3c64xx_dma_buff), GFP_KERNEL);
+	if (!buff) {
+		printk(KERN_ERR "%s: no memory for buffer\n", __func__);
+		return -ENOMEM;
+	}
+
+	lli = dma_pool_alloc(dma_pool, GFP_KERNEL, &buff->lli_dma);
+	if (!lli) {
+		printk(KERN_ERR "%s: no memory for lli\n", __func__);
+		ret = -ENOMEM;
+		goto err_buff;
+	}
+
+	pr_debug("%s: buff %p, dp %08x lli (%p, %08x) %d\n",
+		 __func__, buff, data, lli, (u32)buff->lli_dma, size);
+
+	buff->lli = lli;
+	buff->pw = id;
+
+	s3c64xx_dma_fill_lli(chan, lli, data, size);
+
+	if ((next = chan->next) != NULL) {
+		struct s3c64xx_dma_buff *end = chan->end;
+		struct pl080s_lli *endlli = end->lli;
+
+		pr_debug("enquing onto channel\n");
+
+		end->next = buff;
+		endlli->next_lli = buff->lli_dma;
+
+		if (chan->flags & S3C2410_DMAF_CIRCULAR) {
+			struct s3c64xx_dma_buff *curr = chan->curr;
+			lli->next_lli = curr->lli_dma;
+		}
+
+		if (next == chan->curr) {
+			writel(buff->lli_dma, chan->regs + PL080_CH_LLI);
+			chan->next = buff;
+		}
+
+		show_lli(endlli);
+		chan->end = buff;
+	} else {
+		pr_debug("enquing onto empty channel\n");
+
+		chan->curr = buff;
+		chan->next = buff;
+		chan->end = buff;
+
+		s3c64xx_lli_to_regs(chan, lli);
+	}
+
+	show_lli(lli);
+
+	dbg_showchan(chan);
+	dbg_showbuffs(chan);
+	return 0;
+
+err_buff:
+	kfree(buff);
+	return ret;
+}
+
+EXPORT_SYMBOL(s3c2410_dma_enqueue);
+
+
+int s3c2410_dma_devconfig(int channel,
+			  enum s3c2410_dmasrc source,
+			  unsigned long devaddr)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+	u32 peripheral;
+	u32 config = 0;
+
+	pr_debug("%s: channel %d, source %d, dev %08lx, chan %p\n",
+		 __func__, channel, source, devaddr, chan);
+
+	WARN_ON(!chan);
+	if (!chan)
+		return -EINVAL;
+
+	peripheral = (chan->peripheral & 0xf);
+	chan->source = source;
+	chan->dev_addr = devaddr;
+
+	pr_debug("%s: peripheral %d\n", __func__, peripheral);
+
+	switch (source) {
+	case S3C2410_DMASRC_HW:
+		config = 2 << PL080_CONFIG_FLOW_CONTROL_SHIFT;
+		config |= peripheral << PL080_CONFIG_SRC_SEL_SHIFT;
+		break;
+	case S3C2410_DMASRC_MEM:
+		config = 1 << PL080_CONFIG_FLOW_CONTROL_SHIFT;
+		config |= peripheral << PL080_CONFIG_DST_SEL_SHIFT;
+		break;
+	default:
+		printk(KERN_ERR "%s: bad source\n", __func__);
+		return -EINVAL;
+	}
+
+	/* allow TC and ERR interrupts */
+	config |= PL080_CONFIG_TC_IRQ_MASK;
+	config |= PL080_CONFIG_ERR_IRQ_MASK;
+
+	pr_debug("%s: config %08x\n", __func__, config);
+
+	writel(config, chan->regs + PL080S_CH_CONFIG);
+
+	return 0;
+}
+EXPORT_SYMBOL(s3c2410_dma_devconfig);
+
+
+int s3c2410_dma_getposition(unsigned int channel,
+			    dma_addr_t *src, dma_addr_t *dst)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+
+	WARN_ON(!chan);
+	if (!chan)
+		return -EINVAL;
+
+	if (src != NULL)
+		*src = readl(chan->regs + PL080_CH_SRC_ADDR);
+
+	if (dst != NULL)
+		*dst = readl(chan->regs + PL080_CH_DST_ADDR);
+
+	return 0;
+}
+EXPORT_SYMBOL(s3c2410_dma_getposition);
+
+/* s3c2410_request_dma
+ *
+ * get control of an dma channel
+*/
+
+int s3c2410_dma_request(unsigned int channel,
+			struct s3c2410_dma_client *client,
+			void *dev)
+{
+	struct s3c2410_dma_chan *chan;
+	unsigned long flags;
+
+	pr_debug("dma%d: s3c2410_request_dma: client=%s, dev=%p\n",
+		 channel, client->name, dev);
+
+	local_irq_save(flags);
+
+	chan = s3c64xx_dma_map_channel(channel);
+	if (chan == NULL) {
+		local_irq_restore(flags);
+		return -EBUSY;
+	}
+
+	dbg_showchan(chan);
+
+	chan->client = client;
+	chan->in_use = 1;
+	chan->peripheral = channel;
+
+	local_irq_restore(flags);
+
+	/* need to setup */
+
+	pr_debug("%s: channel initialised, %p\n", __func__, chan);
+
+	return chan->number | DMACH_LOW_LEVEL;
+}
+
+EXPORT_SYMBOL(s3c2410_dma_request);
+
+/* s3c2410_dma_free
+ *
+ * release the given channel back to the system, will stop and flush
+ * any outstanding transfers, and ensure the channel is ready for the
+ * next claimant.
+ *
+ * Note, although a warning is currently printed if the freeing client
+ * info is not the same as the registrant's client info, the free is still
+ * allowed to go through.
+*/
+
+int s3c2410_dma_free(unsigned int channel, struct s3c2410_dma_client *client)
+{
+	struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
+	unsigned long flags;
+
+	if (chan == NULL)
+		return -EINVAL;
+
+	local_irq_save(flags);
+
+	if (chan->client != client) {
+		printk(KERN_WARNING "dma%d: possible free from different client (channel %p, passed %p)\n",
+		       channel, chan->client, client);
+	}
+
+	/* sort out stopping and freeing the channel */
+
+
+	chan->client = NULL;
+	chan->in_use = 0;
+
+	if (!(channel & DMACH_LOW_LEVEL))
+		s3c_dma_chan_map[channel] = NULL;
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+EXPORT_SYMBOL(s3c2410_dma_free);
+
+
+static void s3c64xx_dma_tcirq(struct s3c64xx_dmac *dmac, int offs)
+{
+	struct s3c2410_dma_chan *chan = dmac->channels + offs;
+
+	/* note, we currently do not bother to work out which buffer
+	 * or buffers have been completed since the last tc-irq. */
+
+	if (chan->callback_fn)
+		(chan->callback_fn)(chan, chan->curr->pw, 0, S3C2410_RES_OK);
+}
+
+static void s3c64xx_dma_errirq(struct s3c64xx_dmac *dmac, int offs)
+{
+	printk(KERN_DEBUG "%s: offs %d\n", __func__, offs);
+}
+
+static irqreturn_t s3c64xx_dma_irq(int irq, void *pw)
+{
+	struct s3c64xx_dmac *dmac = pw;
+	u32 tcstat, errstat;
+	u32 bit;
+	int offs;
+
+	tcstat = readl(dmac->regs + PL080_TC_STATUS);
+	errstat = readl(dmac->regs + PL080_ERR_STATUS);
+
+	for (offs = 0, bit = 1; offs < 8; offs++, bit <<= 1) {
+		if (tcstat & bit) {
+			writel(bit, dmac->regs + PL080_TC_CLEAR);
+			s3c64xx_dma_tcirq(dmac, offs);
+		}
+
+		if (errstat & bit) {
+			s3c64xx_dma_errirq(dmac, offs);
+			writel(bit, dmac->regs + PL080_ERR_CLEAR);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static struct sysdev_class dma_sysclass = {
+	.name		= "s3c64xx-dma",
+};
+
+static int s3c64xx_dma_init1(int chno, enum dma_ch chbase,
+			     int irq, unsigned int base)
+{
+	struct s3c2410_dma_chan *chptr = &s3c2410_chans[chno];
+	struct s3c64xx_dmac *dmac;
+	char clkname[16];
+	void __iomem *regs;
+	void __iomem *regptr;
+	int err, ch;
+
+	dmac = kzalloc(sizeof(struct s3c64xx_dmac), GFP_KERNEL);
+	if (!dmac) {
+		printk(KERN_ERR "%s: failed to alloc mem\n", __func__);
+		return -ENOMEM;
+	}
+
+	dmac->sysdev.id = chno / 8;
+	dmac->sysdev.cls = &dma_sysclass;
+
+	err = sysdev_register(&dmac->sysdev);
+	if (err) {
+		printk(KERN_ERR "%s: failed to register sysdevice\n", __func__);
+		goto err_alloc;
+	}
+
+	regs = ioremap(base, 0x200);
+	if (!regs) {
+		printk(KERN_ERR "%s: failed to ioremap()\n", __func__);
+		err = -ENXIO;
+		goto err_dev;
+	}
+
+	snprintf(clkname, sizeof(clkname), "dma%d", dmac->sysdev.id);
+
+	dmac->clk = clk_get(NULL, clkname);
+	if (IS_ERR(dmac->clk)) {
+		printk(KERN_ERR "%s: failed to get clock %s\n", __func__, clkname);
+		err = PTR_ERR(dmac->clk);
+		goto err_map;
+	}
+
+	clk_enable(dmac->clk);
+
+	dmac->regs = regs;
+	dmac->chanbase = chbase;
+	dmac->channels = chptr;
+
+	err = request_irq(irq, s3c64xx_dma_irq, 0, "DMA", dmac);
+	if (err < 0) {
+		printk(KERN_ERR "%s: failed to get irq\n", __func__);
+		goto err_clk;
+	}
+
+	regptr = regs + PL080_Cx_BASE(0);
+
+	for (ch = 0; ch < 8; ch++, chno++, chptr++) {
+		printk(KERN_INFO "%s: registering DMA %d (%p)\n",
+		       __func__, chno, regptr);
+
+		chptr->bit = 1 << ch;
+		chptr->number = chno;
+		chptr->dmac = dmac;
+		chptr->regs = regptr;
+		regptr += PL008_Cx_STRIDE;
+	}
+
+	/* for the moment, permanently enable the controller */
+	writel(PL080_CONFIG_ENABLE, regs + PL080_CONFIG);
+
+	printk(KERN_INFO "PL080: IRQ %d, at %p\n", irq, regs);
+
+	return 0;
+
+err_clk:
+	clk_disable(dmac->clk);
+	clk_put(dmac->clk);
+err_map:
+	iounmap(regs);
+err_dev:
+	sysdev_unregister(&dmac->sysdev);
+err_alloc:
+	kfree(dmac);
+	return err;
+}
+
+static int __init s3c64xx_dma_init(void)
+{
+	int ret;
+
+	printk(KERN_INFO "%s: Registering DMA channels\n", __func__);
+
+	dma_pool = dma_pool_create("DMA-LLI", NULL, 32, 16, 0);
+	if (!dma_pool) {
+		printk(KERN_ERR "%s: failed to create pool\n", __func__);
+		return -ENOMEM;
+	}
+
+	ret = sysdev_class_register(&dma_sysclass);
+	if (ret) {
+		printk(KERN_ERR "%s: failed to create sysclass\n", __func__);
+		return -ENOMEM;
+	}
+
+	/* Set all DMA configuration to be DMA, not SDMA */
+	writel(0xffffff, S3C_SYSREG(0x110));
+
+	/* Register standard DMA controlers */
+	s3c64xx_dma_init1(0, DMACH_UART0, IRQ_DMA0, 0x75000000);
+	s3c64xx_dma_init1(8, DMACH_PCM1_TX, IRQ_DMA1, 0x75100000);
+
+	return 0;
+}
+
+arch_initcall(s3c64xx_dma_init);