1 files changed, 102 insertions, 0 deletions
diff --git a/arch/sh/drivers/dma/dma-pvr2.c b/arch/sh/drivers/dma/dma-pvr2.c
new file mode 100644
index 0000000000..21c347543e
--- /dev/null
+++ b/arch/sh/drivers/dma/dma-pvr2.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/drivers/dma/dma-pvr2.c
+ *
+ * NEC PowerVR 2 (Dreamcast) DMA support
+ *
+ * Copyright (C) 2003, 2004  Paul Mundt
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <mach/sysasic.h>
+#include <mach/dma.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+
+static unsigned int xfer_complete;
+static int count;
+
+static irqreturn_t pvr2_dma_interrupt(int irq, void *dev_id)
+{
+	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 (__raw_readl(PVR2_DMA_MODE) != 0)
+		return -EBUSY;
+
+	__raw_writel(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;
+
+	__raw_writel(chan->dar, PVR2_DMA_ADDR);
+	__raw_writel(chan->count, PVR2_DMA_COUNT);
+	__raw_writel(chan->mode & DMA_MODE_MASK, PVR2_DMA_MODE);
+
+	return 0;
+}
+
+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		= "pvr2_dmac",
+	.nr_channels	= 1,
+	.ops		= &pvr2_dma_ops,
+	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
+};
+
+static int __init pvr2_dma_init(void)
+{
+	if (request_irq(HW_EVENT_PVR2_DMA, pvr2_dma_interrupt, 0,
+			"pvr2 DMA handler", NULL))
+		pr_err("Failed to register pvr2 DMA handler interrupt\n");
+	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);
+	unregister_dmac(&pvr2_dma_info);
+}
+
+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 v2");