--- /dev/null
+/* 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 <mach/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 |= PL080_CONTROL_DST_INCR;
+ break;
+
+ case S3C2410_DMASRC_MEM:
+ src = data;
+ dst = chan->dev_addr;
+ control0 = PL080_CONTROL_DST_AHB2;
+ 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 */
+ control0 |= (u32)chan->hw_width << PL080_CONTROL_DWIDTH_SHIFT;
+ control0 |= (u32)chan->hw_width << PL080_CONTROL_SWIDTH_SHIFT;
+
+ 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;
+ unsigned long flags;
+ int ret;
+
+ WARN_ON(!chan);
+ if (!chan)
+ return -EINVAL;
+
+ buff = kzalloc(sizeof(struct s3c64xx_dma_buff), GFP_ATOMIC);
+ if (!buff) {
+ printk(KERN_ERR "%s: no memory for buffer\n", __func__);
+ return -ENOMEM;
+ }
+
+ lli = dma_pool_alloc(dma_pool, GFP_ATOMIC, &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);
+
+ local_irq_save(flags);
+
+ 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);
+ }
+
+ local_irq_restore(flags);
+
+ 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 irqreturn_t s3c64xx_dma_irq(int irq, void *pw)
+{
+ struct s3c64xx_dmac *dmac = pw;
+ struct s3c2410_dma_chan *chan;
+ enum s3c2410_dma_buffresult res;
+ 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) {
+ struct s3c64xx_dma_buff *buff;
+
+ if (!(errstat & bit) && !(tcstat & bit))
+ continue;
+
+ chan = dmac->channels + offs;
+ res = S3C2410_RES_ERR;
+
+ if (tcstat & bit) {
+ writel(bit, dmac->regs + PL080_TC_CLEAR);
+ res = S3C2410_RES_OK;
+ }
+
+ if (errstat & bit)
+ writel(bit, dmac->regs + PL080_ERR_CLEAR);
+
+ /* 'next' points to the buffer that is next to the
+ * currently active buffer.
+ * For CIRCULAR queues, 'next' will be same as 'curr'
+ * when 'end' is the active buffer.
+ */
+ buff = chan->curr;
+ while (buff && buff != chan->next
+ && buff->next != chan->next)
+ buff = buff->next;
+
+ if (!buff)
+ BUG();
+
+ if (buff == chan->next)
+ buff = chan->end;
+
+ s3c64xx_dma_bufffdone(chan, buff, res);
+
+ /* Free the node and update curr, if non-circular queue */
+ if (!(chan->flags & S3C2410_DMAF_CIRCULAR)) {
+ chan->curr = buff->next;
+ s3c64xx_dma_freebuff(buff);
+ }
+
+ /* Update 'next' */
+ buff = chan->next;
+ if (chan->next == chan->end) {
+ chan->next = chan->curr;
+ if (!(chan->flags & S3C2410_DMAF_CIRCULAR))
+ chan->end = NULL;
+ } else {
+ chan->next = buff->next;
+ }
+ }
+
+ 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, sizeof(struct pl080s_lli), 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);
projects / firefly-linux-kernel-4.4.55.git / blobdiff