Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

arch/sh/drivers/dma/Kconfig

@@ -0,0 +1,55 @@
+menu "DMA support"
+
+config SH_DMA
+	bool "DMA controller (DMAC) support"
+	help
+	  Selecting this option will provide same API as PC's Direct Memory
+	  Access Controller(8237A) for SuperH DMAC.
+
+	  If unsure, say N.
+
+config NR_ONCHIP_DMA_CHANNELS
+	depends on SH_DMA
+	int "Number of on-chip DMAC channels"
+	default "4"
+	help
+	  This allows you to specify the number of channels that the on-chip
+	  DMAC supports. This will be 4 for SH7750/SH7751 and 8 for the
+	  SH7750R/SH7751R.
+
+config NR_DMA_CHANNELS_BOOL
+	depends on SH_DMA
+	bool "Override default number of maximum DMA channels"
+	help
+	  This allows you to forcibly update the maximum number of supported
+	  DMA channels for a given board. If this is unset, this will default
+	  to the number of channels that the on-chip DMAC has.
+
+config NR_DMA_CHANNELS
+	int "Maximum number of DMA channels"
+	depends on SH_DMA && NR_DMA_CHANNELS_BOOL
+	default NR_ONCHIP_DMA_CHANNELS
+	help
+	  This allows you to specify the maximum number of DMA channels to
+	  support. Setting this to a higher value allows for cascading DMACs
+	  with additional channels.
+
+config DMA_PAGE_OPS
+	bool "Use DMAC for page copy/clear"
+	depends on SH_DMA && BROKEN
+	help
+	  Selecting this option will use a dual-address mode configured channel
+	  in the SH DMAC for copy_page()/clear_page(). Primarily a performance
+	  hack.
+
+config DMA_PAGE_OPS_CHANNEL
+	depends on DMA_PAGE_OPS
+	int "DMA channel for sh memory-manager page copy/clear"
+	default "3"
+	help
+	  This allows the specification of the dual address dma channel,
+	  in case channel 3 is unavailable. On the SH4, channels 1,2, and 3
+	  are dual-address capable.
+
+endmenu
+

arch/sh/drivers/dma/Makefile

@@ -0,0 +1,9 @@
+#
+# Makefile for the SuperH DMA specific kernel interface routines under Linux.
+#
+
+obj-y				+= dma-api.o dma-isa.o
+obj-$(CONFIG_SYSFS)		+= dma-sysfs.o
+obj-$(CONFIG_SH_DMA)		+= dma-sh.o
+obj-$(CONFIG_SH_DREAMCAST)	+= dma-pvr2.o dma-g2.o
+

arch/sh/drivers/dma/dma-api.c

@@ -0,0 +1,292 @@
+/*
+ * arch/sh/drivers/dma/dma-api.c
+ *
+ * SuperH-specific DMA management API
+ *
+ * Copyright (C) 2003, 2004  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/proc_fs.h>
+#include <linux/list.h>
+#include <asm/dma.h>
+
+DEFINE_SPINLOCK(dma_spin_lock);
+static LIST_HEAD(registered_dmac_list);
+
+/*
+ * A brief note about the reasons for this API as it stands.
+ *
+ * For starters, the old ISA DMA API didn't work for us for a number of
+ * reasons, for one, the vast majority of channels on the SH DMAC are
+ * dual-address mode only, and both the new and the old DMA APIs are after the
+ * concept of managing a DMA buffer, which doesn't overly fit this model very
+ * well. In addition to which, the new API is largely geared at IOMMUs and
+ * GARTs, and doesn't even support the channel notion very well.
+ *
+ * The other thing that's a marginal issue, is the sheer number of random DMA
+ * engines that are present (ie, in boards like the Dreamcast), some of which
+ * cascade off of the SH DMAC, and others do not. As such, there was a real
+ * need for a scalable subsystem that could deal with both single and
+ * dual-address mode usage, in addition to interoperating with cascaded DMACs.
+ *
+ * There really isn't any reason why this needs to be SH specific, though I'm
+ * not aware of too many other processors (with the exception of some MIPS)
+ * that have the same concept of a dual address mode, or any real desire to
+ * actually make use of the DMAC even if such a subsystem were exposed
+ * elsewhere.
+ *
+ * The idea for this was derived from the ARM port, which acted as an excellent
+ * reference when trying to address these issues.
+ *
+ * It should also be noted that the decision to add Yet Another DMA API(tm) to
+ * the kernel wasn't made easily, and was only decided upon after conferring
+ * with jejb with regards to the state of the old and new APIs as they applied
+ * to these circumstances. Philip Blundell was also a great help in figuring
+ * out some single-address mode DMA semantics that were otherwise rather
+ * confusing.
+ */
+
+struct dma_info *get_dma_info(unsigned int chan)
+{
+	struct list_head *pos, *tmp;
+	unsigned int total = 0;
+
+	/*
+	 * Look for each DMAC's range to determine who the owner of
+	 * the channel is.
+	 */
+	list_for_each_safe(pos, tmp, &registered_dmac_list) {
+		struct dma_info *info = list_entry(pos, struct dma_info, list);
+
+		total += info->nr_channels;
+		if (chan > total)
+			continue;
+
+		return info;
+	}
+
+	return NULL;
+}
+
+struct dma_channel *get_dma_channel(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+
+	if (!info)
+		return ERR_PTR(-EINVAL);
+
+	return info->channels + chan;
+}
+
+int get_dma_residue(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	if (info->ops->get_residue)
+		return info->ops->get_residue(channel);
+
+	return 0;
+}
+
+int request_dma(unsigned int chan, const char *dev_id)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	down(&channel->sem);
+
+	if (!info->ops || chan >= MAX_DMA_CHANNELS) {
+		up(&channel->sem);
+		return -EINVAL;
+	}
+
+	atomic_set(&channel->busy, 1);
+
+	strlcpy(channel->dev_id, dev_id, sizeof(channel->dev_id));
+
+	up(&channel->sem);
+
+	if (info->ops->request)
+		return info->ops->request(channel);
+
+	return 0;
+}
+
+void free_dma(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	if (info->ops->free)
+		info->ops->free(channel);
+
+	atomic_set(&channel->busy, 0);
+}
+
+void dma_wait_for_completion(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	if (channel->flags & DMA_TEI_CAPABLE) {
+		wait_event(channel->wait_queue,
+			   (info->ops->get_residue(channel) == 0));
+		return;
+	}
+
+	while (info->ops->get_residue(channel))
+		cpu_relax();
+}
+
+void dma_configure_channel(unsigned int chan, unsigned long flags)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	if (info->ops->configure)
+		info->ops->configure(channel, flags);
+}
+
+int dma_xfer(unsigned int chan, unsigned long from,
+	     unsigned long to, size_t size, unsigned int mode)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	channel->sar	= from;
+	channel->dar	= to;
+	channel->count	= size;
+	channel->mode	= mode;
+
+	return info->ops->xfer(channel);
+}
+
+#ifdef CONFIG_PROC_FS
+static int dma_read_proc(char *buf, char **start, off_t off,
+			 int len, int *eof, void *data)
+{
+	struct list_head *pos, *tmp;
+	char *p = buf;
+
+	if (list_empty(&registered_dmac_list))
+		return 0;
+
+	/*
+	 * Iterate over each registered DMAC
+	 */
+	list_for_each_safe(pos, tmp, &registered_dmac_list) {
+		struct dma_info *info = list_entry(pos, struct dma_info, list);
+		int i;
+
+		/*
+		 * Iterate over each channel
+		 */
+		for (i = 0; i < info->nr_channels; i++) {
+			struct dma_channel *channel = info->channels + i;
+
+			if (!(channel->flags & DMA_CONFIGURED))
+				continue;
+
+			p += sprintf(p, "%2d: %14s    %s\n", i,
+				     info->name, channel->dev_id);
+		}
+	}
+
+	return p - buf;
+}
+#endif
+
+
+int __init register_dmac(struct dma_info *info)
+{
+	int i;
+
+	INIT_LIST_HEAD(&info->list);
+
+	printk(KERN_INFO "DMA: Registering %s handler (%d channel%s).\n",
+	       info->name, info->nr_channels,
+	       info->nr_channels > 1 ? "s" : "");
+
+	BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels);
+
+	/*
+	 * Don't touch pre-configured channels
+	 */
+	if (!(info->flags & DMAC_CHANNELS_CONFIGURED)) {
+		unsigned int size;
+
+		size = sizeof(struct dma_channel) * info->nr_channels;
+
+		info->channels = kmalloc(size, GFP_KERNEL);
+		if (!info->channels)
+			return -ENOMEM;
+
+		memset(info->channels, 0, size);
+	}
+
+	for (i = 0; i < info->nr_channels; i++) {
+		struct dma_channel *chan = info->channels + i;
+
+		chan->chan = i;
+
+		memcpy(chan->dev_id, "Unused", 7);
+
+		if (info->flags & DMAC_CHANNELS_TEI_CAPABLE)
+			chan->flags |= DMA_TEI_CAPABLE;
+
+		init_MUTEX(&chan->sem);
+		init_waitqueue_head(&chan->wait_queue);
+
+#ifdef CONFIG_SYSFS
+		dma_create_sysfs_files(chan);
+#endif
+	}
+
+	list_add(&info->list, &registered_dmac_list);
+
+	return 0;
+}
+
+void __exit unregister_dmac(struct dma_info *info)
+{
+	if (!(info->flags & DMAC_CHANNELS_CONFIGURED))
+		kfree(info->channels);
+
+	list_del(&info->list);
+}
+
+static int __init dma_api_init(void)
+{
+	printk("DMA: Registering DMA API.\n");
+
+#ifdef CONFIG_PROC_FS
+	create_proc_read_entry("dma", 0, 0, dma_read_proc, 0);
+#endif
+
+	return 0;
+}
+
+subsys_initcall(dma_api_init);
+
+MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_DESCRIPTION("DMA API for SuperH");
+MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL(request_dma);
+EXPORT_SYMBOL(free_dma);
+EXPORT_SYMBOL(register_dmac);
+EXPORT_SYMBOL(get_dma_residue);
+EXPORT_SYMBOL(get_dma_info);
+EXPORT_SYMBOL(get_dma_channel);
+EXPORT_SYMBOL(dma_xfer);
+EXPORT_SYMBOL(dma_wait_for_completion);
+EXPORT_SYMBOL(dma_configure_channel);
+

arch/sh/drivers/dma/dma-g2.c

@@ -0,0 +1,171 @@
+/*
+ * arch/sh/drivers/dma/dma-g2.c
+ *
+ * G2 bus DMA support
+ *
+ * Copyright (C) 2003, 2004  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+
+#include <asm/mach/sysasic.h>
+#include <asm/mach/dma.h>
+#include <asm/dma.h>
+
+struct g2_channel {
+	unsigned long g2_addr;		/* G2 bus address */
+	unsigned long root_addr;	/* Root bus (SH-4) address */
+	unsigned long size;		/* Size (in bytes), 32-byte aligned */
+	unsigned long direction;	/* Transfer direction */
+	unsigned long ctrl;		/* Transfer control */
+	unsigned long chan_enable;	/* Channel enable */
+	unsigned long xfer_enable;	/* Transfer enable */
+	unsigned long xfer_stat;	/* Transfer status */
+} __attribute__ ((aligned(32)));
+
+struct g2_status {
+	unsigned long g2_addr;
+	unsigned long root_addr;
+	unsigned long size;
+	unsigned long status;
+} __attribute__ ((aligned(16)));
+
+struct g2_dma_info {
+	struct g2_channel channel[G2_NR_DMA_CHANNELS];
+	unsigned long pad1[G2_NR_DMA_CHANNELS];
+	unsigned long wait_state;
+	unsigned long pad2[10];
+	unsigned long magic;
+	struct g2_status status[G2_NR_DMA_CHANNELS];
+} __attribute__ ((aligned(256)));
+
+static volatile struct g2_dma_info *g2_dma = (volatile struct g2_dma_info *)0xa05f7800;
+
+static irqreturn_t g2_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	/* FIXME: Do some meaningful completion work here.. */
+	return IRQ_HANDLED;
+}
+
+static struct irqaction g2_dma_irq = {
+	.name		= "g2 DMA handler",
+	.handler	= g2_dma_interrupt,
+	.flags		= SA_INTERRUPT,
+};
+
+static int g2_enable_dma(struct dma_channel *chan)
+{
+	unsigned int chan_nr = chan->chan;
+
+	g2_dma->channel[chan_nr].chan_enable = 1;
+	g2_dma->channel[chan_nr].xfer_enable = 1;
+
+	return 0;
+}
+
+static int g2_disable_dma(struct dma_channel *chan)
+{
+	unsigned int chan_nr = chan->chan;
+
+	g2_dma->channel[chan_nr].chan_enable = 0;
+	g2_dma->channel[chan_nr].xfer_enable = 0;
+
+	return 0;
+}
+
+static int g2_xfer_dma(struct dma_channel *chan)
+{
+	unsigned int chan_nr = chan->chan;
+
+	if (chan->sar & 31) {
+		printk("g2dma: unaligned source 0x%lx\n", chan->sar);
+		return -EINVAL;
+	}
+
+	if (chan->dar & 31) {
+		printk("g2dma: unaligned dest 0x%lx\n", chan->dar);
+		return -EINVAL;
+	}
+
+	/* Align the count */
+	if (chan->count & 31)
+		chan->count = (chan->count + (32 - 1)) & ~(32 - 1);
+
+	/* Fixup destination */
+	chan->dar += 0xa0800000;
+
+	/* Fixup direction */
+	chan->mode = !chan->mode;
+
+	flush_icache_range((unsigned long)chan->sar, chan->count);
+
+	g2_disable_dma(chan);
+
+	g2_dma->channel[chan_nr].g2_addr   = chan->dar & 0x1fffffe0;
+	g2_dma->channel[chan_nr].root_addr = chan->sar & 0x1fffffe0;
+	g2_dma->channel[chan_nr].size	   = (chan->count & ~31) | 0x80000000;
+	g2_dma->channel[chan_nr].direction = chan->mode;
+
+	/*
+	 * bit 0 - ???
+	 * bit 1 - if set, generate a hardware event on transfer completion
+	 * bit 2 - ??? something to do with suspend?
+	 */
+	g2_dma->channel[chan_nr].ctrl	= 5; /* ?? */
+
+	g2_enable_dma(chan);
+
+	/* debug cruft */
+	pr_debug("count, sar, dar, mode, ctrl, chan, xfer: %ld, 0x%08lx, "
+		 "0x%08lx, %ld, %ld, %ld, %ld\n",
+		 g2_dma->channel[chan_nr].size,
+		 g2_dma->channel[chan_nr].root_addr,
+		 g2_dma->channel[chan_nr].g2_addr,
+		 g2_dma->channel[chan_nr].direction,
+		 g2_dma->channel[chan_nr].ctrl,
+		 g2_dma->channel[chan_nr].chan_enable,
+		 g2_dma->channel[chan_nr].xfer_enable);
+
+	return 0;
+}
+
+static struct dma_ops g2_dma_ops = {
+	.xfer		= g2_xfer_dma,
+};
+
+static struct dma_info g2_dma_info = {
+	.name		= "G2 DMA",
+	.nr_channels	= 4,
+	.ops		= &g2_dma_ops,
+	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
+};
+
+static int __init g2_dma_init(void)
+{
+	setup_irq(HW_EVENT_G2_DMA, &g2_dma_irq);
+
+	/* Magic */
+	g2_dma->wait_state	= 27;
+	g2_dma->magic		= 0x4659404f;
+
+	return register_dmac(&g2_dma_info);
+}
+
+static void __exit g2_dma_exit(void)
+{
+	free_irq(HW_EVENT_G2_DMA, 0);
+}
+
+subsys_initcall(g2_dma_init);
+module_exit(g2_dma_exit);
+
+MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_DESCRIPTION("G2 bus DMA driver");
+MODULE_LICENSE("GPL");
+

arch/sh/drivers/dma/dma-isa.c

@@ -0,0 +1,106 @@
+/*
+ * arch/sh/drivers/dma/dma-isa.c
+ *
+ * Generic ISA DMA wrapper for SH DMA API
+ *
+ * Copyright (C) 2003, 2004  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/dma.h>
+
+/*
+ * This implements a small wrapper set to make code using the old ISA DMA API
+ * work with the SH DMA API. Since most of the work in the new API happens
+ * at ops->xfer() time, we simply use the various set_dma_xxx() routines to
+ * fill in per-channel info, and then hand hand this off to ops->xfer() at
+ * enable_dma() time.
+ *
+ * For channels that are doing on-demand data transfer via cascading, the
+ * channel itself will still need to be configured through the new API. As
+ * such, this code is meant for only the simplest of tasks (and shouldn't be
+ * used in any new drivers at all).
+ *
+ * It should also be noted that various functions here are labelled as
+ * being deprecated. This is due to the fact that the ops->xfer() method is
+ * the preferred way of doing things (as well as just grabbing the spinlock
+ * directly). As such, any users of this interface will be warned rather
+ * loudly.
+ */
+
+unsigned long __deprecated claim_dma_lock(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dma_spin_lock, flags);
+
+	return flags;
+}
+EXPORT_SYMBOL(claim_dma_lock);
+
+void __deprecated release_dma_lock(unsigned long flags)
+{
+	spin_unlock_irqrestore(&dma_spin_lock, flags);
+}
+EXPORT_SYMBOL(release_dma_lock);
+
+void __deprecated disable_dma(unsigned int chan)
+{
+	/* Nothing */
+}
+EXPORT_SYMBOL(disable_dma);
+
+void __deprecated enable_dma(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	info->ops->xfer(channel);
+}
+EXPORT_SYMBOL(enable_dma);
+
+void clear_dma_ff(unsigned int chan)
+{
+	/* Nothing */
+}
+EXPORT_SYMBOL(clear_dma_ff);
+
+void set_dma_mode(unsigned int chan, char mode)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	channel->mode = mode;
+}
+EXPORT_SYMBOL(set_dma_mode);
+
+void set_dma_addr(unsigned int chan, unsigned int addr)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	/*
+	 * Single address mode is the only thing supported through
+	 * this interface.
+	 */
+	if ((channel->mode & DMA_MODE_MASK) == DMA_MODE_READ) {
+		channel->sar = addr;
+	} else {
+		channel->dar = addr;
+	}
+}
+EXPORT_SYMBOL(set_dma_addr);
+
+void set_dma_count(unsigned int chan, unsigned int count)
+{
+	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
+
+	channel->count = count;
+}
+EXPORT_SYMBOL(set_dma_count);
+

arch/sh/drivers/dma/dma-pvr2.c

@@ -0,0 +1,109 @@
+/*
+ * arch/sh/boards/dreamcast/dma-pvr2.c
+ *
+ * NEC PowerVR 2 (Dreamcast) DMA support
+ *
+ * Copyright (C) 2003, 2004  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <asm/mach/sysasic.h>
+#include <asm/mach/dma.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+
+static unsigned int xfer_complete = 0;
+static int count = 0;
+
+static irqreturn_t pvr2_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	if (get_dma_residue(PVR2_CASCADE_CHAN)) {
+		printk(KERN_WARNING "DMA: SH DMAC did not complete transfer "
+		       "on channel %d, waiting..\n", PVR2_CASCADE_CHAN);
+		dma_wait_for_completion(PVR2_CASCADE_CHAN);
+	}
+
+	if (count++ < 10)
+		pr_debug("Got a pvr2 dma interrupt for channel %d\n",
+			 irq - HW_EVENT_PVR2_DMA);
+
+	xfer_complete = 1;
+
+	return IRQ_HANDLED;
+}
+
+static int pvr2_request_dma(struct dma_channel *chan)
+{
+	if (ctrl_inl(PVR2_DMA_MODE) != 0)
+		return -EBUSY;
+
+	ctrl_outl(0, PVR2_DMA_LMMODE0);
+
+	return 0;
+}
+
+static int pvr2_get_dma_residue(struct dma_channel *chan)
+{
+	return xfer_complete == 0;
+}
+
+static int pvr2_xfer_dma(struct dma_channel *chan)
+{
+	if (chan->sar || !chan->dar)
+		return -EINVAL;
+
+	xfer_complete = 0;
+
+	ctrl_outl(chan->dar, PVR2_DMA_ADDR);
+	ctrl_outl(chan->count, PVR2_DMA_COUNT);
+	ctrl_outl(chan->mode & DMA_MODE_MASK, PVR2_DMA_MODE);
+
+	return 0;
+}
+
+static struct irqaction pvr2_dma_irq = {
+	.name		= "pvr2 DMA handler",
+	.handler	= pvr2_dma_interrupt,
+	.flags		= SA_INTERRUPT,
+};
+
+static struct dma_ops pvr2_dma_ops = {
+	.request	= pvr2_request_dma,
+	.get_residue	= pvr2_get_dma_residue,
+	.xfer		= pvr2_xfer_dma,
+};
+
+static struct dma_info pvr2_dma_info = {
+	.name		= "PowerVR 2 DMA",
+	.nr_channels	= 1,
+	.ops		= &pvr2_dma_ops,
+	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
+};
+
+static int __init pvr2_dma_init(void)
+{
+	setup_irq(HW_EVENT_PVR2_DMA, &pvr2_dma_irq);
+	request_dma(PVR2_CASCADE_CHAN, "pvr2 cascade");
+
+	return register_dmac(&pvr2_dma_info);
+}
+
+static void __exit pvr2_dma_exit(void)
+{
+	free_dma(PVR2_CASCADE_CHAN);
+	free_irq(HW_EVENT_PVR2_DMA, 0);
+}
+
+subsys_initcall(pvr2_dma_init);
+module_exit(pvr2_dma_exit);
+
+MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_DESCRIPTION("NEC PowerVR 2 DMA driver");
+MODULE_LICENSE("GPL");
+

arch/sh/drivers/dma/dma-sh.c

@@ -0,0 +1,267 @@
+/*
+ * arch/sh/drivers/dma/dma-sh.c
+ *
+ * SuperH On-chip DMAC Support
+ *
+ * Copyright (C) 2000 Takashi YOSHII
+ * Copyright (C) 2003, 2004 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <asm/signal.h>
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+#include "dma-sh.h"
+
+/*
+ * The SuperH DMAC supports a number of transmit sizes, we list them here,
+ * with their respective values as they appear in the CHCR registers.
+ *
+ * Defaults to a 64-bit transfer size.
+ */
+enum {
+	XMIT_SZ_64BIT,
+	XMIT_SZ_8BIT,
+	XMIT_SZ_16BIT,
+	XMIT_SZ_32BIT,
+	XMIT_SZ_256BIT,
+};
+
+/*
+ * The DMA count is defined as the number of bytes to transfer.
+ */
+static unsigned int ts_shift[] = {
+	[XMIT_SZ_64BIT]		= 3,
+	[XMIT_SZ_8BIT]		= 0,
+	[XMIT_SZ_16BIT]		= 1,
+	[XMIT_SZ_32BIT]		= 2,
+	[XMIT_SZ_256BIT]	= 5,
+};
+
+static inline unsigned int get_dmte_irq(unsigned int chan)
+{
+	unsigned int irq;
+
+	/*
+	 * Normally we could just do DMTE0_IRQ + chan outright, though in the
+	 * case of the 7751R, the DMTE IRQs for channels > 4 start right above
+	 * the SCIF
+	 */
+
+	if (chan < 4) {
+		irq = DMTE0_IRQ + chan;
+	} else {
+		irq = DMTE4_IRQ + chan - 4;
+	}
+
+	return irq;
+}
+
+/*
+ * We determine the correct shift size based off of the CHCR transmit size
+ * for the given channel. Since we know that it will take:
+ *
+ *	info->count >> ts_shift[transmit_size]
+ *
+ * iterations to complete the transfer.
+ */
+static inline unsigned int calc_xmit_shift(struct dma_channel *chan)
+{
+	u32 chcr = ctrl_inl(CHCR[chan->chan]);
+
+	chcr >>= 4;
+
+	return ts_shift[chcr & 0x0007];
+}
+
+/*
+ * The transfer end interrupt must read the chcr register to end the
+ * hardware interrupt active condition.
+ * Besides that it needs to waken any waiting process, which should handle
+ * setting up the next transfer.
+ */
+static irqreturn_t dma_tei(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct dma_channel *chan = (struct dma_channel *)dev_id;
+	u32 chcr;
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
+
+	if (!(chcr & CHCR_TE))
+		return IRQ_NONE;
+
+	chcr &= ~(CHCR_IE | CHCR_DE);
+	ctrl_outl(chcr, CHCR[chan->chan]);
+
+	wake_up(&chan->wait_queue);
+
+	return IRQ_HANDLED;
+}
+
+static int sh_dmac_request_dma(struct dma_channel *chan)
+{
+	return request_irq(get_dmte_irq(chan->chan), dma_tei,
+			   SA_INTERRUPT, "DMAC Transfer End", chan);
+}
+
+static void sh_dmac_free_dma(struct dma_channel *chan)
+{
+	free_irq(get_dmte_irq(chan->chan), chan);
+}
+
+static void sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr)
+{
+	if (!chcr)
+		chcr = RS_DUAL;
+
+	ctrl_outl(chcr, CHCR[chan->chan]);
+
+	chan->flags |= DMA_CONFIGURED;
+}
+
+static void sh_dmac_enable_dma(struct dma_channel *chan)
+{
+	int irq = get_dmte_irq(chan->chan);
+	u32 chcr;
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
+	chcr |= CHCR_DE | CHCR_IE;
+	ctrl_outl(chcr, CHCR[chan->chan]);
+
+	enable_irq(irq);
+}
+
+static void sh_dmac_disable_dma(struct dma_channel *chan)
+{
+	int irq = get_dmte_irq(chan->chan);
+	u32 chcr;
+
+	disable_irq(irq);
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
+	chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
+	ctrl_outl(chcr, CHCR[chan->chan]);
+}
+
+static int sh_dmac_xfer_dma(struct dma_channel *chan)
+{
+	/*
+	 * If we haven't pre-configured the channel with special flags, use
+	 * the defaults.
+	 */
+	if (!(chan->flags & DMA_CONFIGURED))
+		sh_dmac_configure_channel(chan, 0);
+
+	sh_dmac_disable_dma(chan);
+
+	/*
+	 * Single-address mode usage note!
+	 *
+	 * It's important that we don't accidentally write any value to SAR/DAR
+	 * (this includes 0) that hasn't been directly specified by the user if
+	 * we're in single-address mode.
+	 *
+	 * In this case, only one address can be defined, anything else will
+	 * result in a DMA address error interrupt (at least on the SH-4),
+	 * which will subsequently halt the transfer.
+	 *
+	 * Channel 2 on the Dreamcast is a special case, as this is used for
+	 * cascading to the PVR2 DMAC. In this case, we still need to write
+	 * SAR and DAR, regardless of value, in order for cascading to work.
+	 */
+	if (chan->sar || (mach_is_dreamcast() && chan->chan == 2))
+		ctrl_outl(chan->sar, SAR[chan->chan]);
+	if (chan->dar || (mach_is_dreamcast() && chan->chan == 2))
+		ctrl_outl(chan->dar, DAR[chan->chan]);
+
+	ctrl_outl(chan->count >> calc_xmit_shift(chan), DMATCR[chan->chan]);
+
+	sh_dmac_enable_dma(chan);
+
+	return 0;
+}
+
+static int sh_dmac_get_dma_residue(struct dma_channel *chan)
+{
+	if (!(ctrl_inl(CHCR[chan->chan]) & CHCR_DE))
+		return 0;
+
+	return ctrl_inl(DMATCR[chan->chan]) << calc_xmit_shift(chan);
+}
+
+#if defined(CONFIG_CPU_SH4)
+static irqreturn_t dma_err(int irq, void *dev_id, struct pt_regs *regs)
+{
+	unsigned long dmaor = ctrl_inl(DMAOR);
+
+	printk("DMAE: DMAOR=%lx\n", dmaor);
+
+	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_NMIF, DMAOR);
+	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_AE, DMAOR);
+	ctrl_outl(ctrl_inl(DMAOR)|DMAOR_DME, DMAOR);
+
+	disable_irq(irq);
+
+	return IRQ_HANDLED;
+}
+#endif
+
+static struct dma_ops sh_dmac_ops = {
+	.request	= sh_dmac_request_dma,
+	.free		= sh_dmac_free_dma,
+	.get_residue	= sh_dmac_get_dma_residue,
+	.xfer		= sh_dmac_xfer_dma,
+	.configure	= sh_dmac_configure_channel,
+};
+
+static struct dma_info sh_dmac_info = {
+	.name		= "SuperH DMAC",
+	.nr_channels	= 4,
+	.ops		= &sh_dmac_ops,
+	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
+};
+
+static int __init sh_dmac_init(void)
+{
+	struct dma_info *info = &sh_dmac_info;
+	int i;
+
+#ifdef CONFIG_CPU_SH4
+	make_ipr_irq(DMAE_IRQ, DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
+	i = request_irq(DMAE_IRQ, dma_err, SA_INTERRUPT, "DMAC Address Error", 0);
+	if (i < 0)
+		return i;
+#endif
+
+	for (i = 0; i < info->nr_channels; i++) {
+		int irq = get_dmte_irq(i);
+
+		make_ipr_irq(irq, DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
+	}
+
+	ctrl_outl(0x8000 | DMAOR_DME, DMAOR);
+
+	return register_dmac(info);
+}
+
+static void __exit sh_dmac_exit(void)
+{
+#ifdef CONFIG_CPU_SH4
+	free_irq(DMAE_IRQ, 0);
+#endif
+}
+
+subsys_initcall(sh_dmac_init);
+module_exit(sh_dmac_exit);
+
+MODULE_LICENSE("GPL");
+

arch/sh/drivers/dma/dma-sh.h

@@ -0,0 +1,52 @@
+/*
+ * arch/sh/drivers/dma/dma-sh.h
+ *
+ * Copyright (C) 2000  Takashi YOSHII
+ * Copyright (C) 2003  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#ifndef __DMA_SH_H
+#define __DMA_SH_H
+
+/* Definitions for the SuperH DMAC */
+#define REQ_L	0x00000000
+#define REQ_E	0x00080000
+#define RACK_H	0x00000000
+#define RACK_L	0x00040000
+#define ACK_R	0x00000000
+#define ACK_W	0x00020000
+#define ACK_H	0x00000000
+#define ACK_L	0x00010000
+#define DM_INC	0x00004000
+#define DM_DEC	0x00008000
+#define SM_INC	0x00001000
+#define SM_DEC	0x00002000
+#define RS_IN	0x00000200
+#define RS_OUT	0x00000300
+#define TM_BURST 0x0000080
+#define TS_8	0x00000010
+#define TS_16	0x00000020
+#define TS_32	0x00000030
+#define TS_64	0x00000000
+#define TS_BLK	0x00000040
+#define CHCR_DE 0x00000001
+#define CHCR_TE 0x00000002
+#define CHCR_IE 0x00000004
+
+/* Define the default configuration for dual address memory-memory transfer.
+ * The 0x400 value represents auto-request, external->external.
+ */
+#define RS_DUAL	(DM_INC | SM_INC | 0x400 | TS_32)
+
+#define DMAOR_COD	0x00000008
+#define DMAOR_AE	0x00000004
+#define DMAOR_NMIF	0x00000002
+#define DMAOR_DME	0x00000001
+
+#define MAX_DMAC_CHANNELS	(CONFIG_NR_ONCHIP_DMA_CHANNELS)
+
+#endif /* __DMA_SH_H */
+

arch/sh/drivers/dma/dma-sysfs.c

@@ -0,0 +1,133 @@
+/*
+ * arch/sh/drivers/dma/dma-sysfs.c
+ *
+ * sysfs interface for SH DMA API
+ *
+ * Copyright (C) 2004  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sysdev.h>
+#include <linux/module.h>
+#include <asm/dma.h>
+
+static struct sysdev_class dma_sysclass = {
+	set_kset_name("dma"),
+};
+
+EXPORT_SYMBOL(dma_sysclass);
+
+static ssize_t dma_show_devices(struct sys_device *dev, char *buf)
+{
+	ssize_t len = 0;
+	int i;
+
+	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
+		struct dma_info *info = get_dma_info(i);
+		struct dma_channel *channel = &info->channels[i];
+
+		len += sprintf(buf + len, "%2d: %14s    %s\n",
+			       channel->chan, info->name,
+			       channel->dev_id);
+	}
+
+	return len;
+}
+
+static SYSDEV_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
+
+static int __init dma_sysclass_init(void)
+{
+	int ret;
+
+	ret = sysdev_class_register(&dma_sysclass);
+	if (ret == 0)
+		sysfs_create_file(&dma_sysclass.kset.kobj, &attr_devices.attr);
+
+	return ret;
+}
+
+postcore_initcall(dma_sysclass_init);
+
+static ssize_t dma_show_dev_id(struct sys_device *dev, char *buf)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	return sprintf(buf, "%s\n", channel->dev_id);
+}
+
+static ssize_t dma_store_dev_id(struct sys_device *dev,
+				const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	strcpy(channel->dev_id, buf);
+	return count;
+}
+
+static SYSDEV_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
+
+static ssize_t dma_store_config(struct sys_device *dev,
+				const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	unsigned long config;
+
+	config = simple_strtoul(buf, NULL, 0);
+	dma_configure_channel(channel->chan, config);
+
+	return count;
+}
+
+static SYSDEV_ATTR(config, S_IWUSR, NULL, dma_store_config);
+
+static ssize_t dma_show_mode(struct sys_device *dev, char *buf)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	return sprintf(buf, "0x%08x\n", channel->mode);
+}
+
+static ssize_t dma_store_mode(struct sys_device *dev,
+			      const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	channel->mode = simple_strtoul(buf, NULL, 0);
+	return count;
+}
+
+static SYSDEV_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
+
+#define dma_ro_attr(field, fmt)						\
+static ssize_t dma_show_##field(struct sys_device *dev, char *buf)	\
+{									\
+	struct dma_channel *channel = to_dma_channel(dev);		\
+	return sprintf(buf, fmt, channel->field);			\
+}									\
+static SYSDEV_ATTR(field, S_IRUGO, dma_show_##field, NULL);
+
+dma_ro_attr(count, "0x%08x\n");
+dma_ro_attr(flags, "0x%08lx\n");
+
+int __init dma_create_sysfs_files(struct dma_channel *chan)
+{
+	struct sys_device *dev = &chan->dev;
+	int ret;
+
+	dev->id  = chan->chan;
+	dev->cls = &dma_sysclass;
+
+	ret = sysdev_register(dev);
+	if (ret)
+		return ret;
+
+	sysdev_create_file(dev, &attr_dev_id);
+	sysdev_create_file(dev, &attr_count);
+	sysdev_create_file(dev, &attr_mode);
+	sysdev_create_file(dev, &attr_flags);
+	sysdev_create_file(dev, &attr_config);
+
+	return 0;
+}
+