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 000000000000..1c0f51cbcd89
--- /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;
+
+        printk("%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);