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authorLars-Peter Clausen <lars@metafoo.de>2010-06-19 04:08:14 +0000
committerRalf Baechle <ralf@linux-mips.org>2010-08-05 13:26:15 +0100
commit68fcfe7f82f46cc2d0c28128afafbd3a3ff874f8 (patch)
tree52bf893dbf3321ed07677592d16dedcb232f9718 /arch/mips/jz4740
parenta55f4506652cbdf23fa1b5fd509d4f3cc01e1843 (diff)
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MIPS: JZ4740: Add DMA support.
Add support for DMA transfers on JZ4740 SoCs. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/1401/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/jz4740')
-rw-r--r--arch/mips/jz4740/dma.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/arch/mips/jz4740/dma.c b/arch/mips/jz4740/dma.c
new file mode 100644
index 0000000..5ebe75a
--- /dev/null
+++ b/arch/mips/jz4740/dma.c
@@ -0,0 +1,289 @@
+/*
+ * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ * JZ4740 SoC DMA support
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+
+#include <linux/dma-mapping.h>
+#include <asm/mach-jz4740/dma.h>
+#include <asm/mach-jz4740/base.h>
+
+#define JZ_REG_DMA_SRC_ADDR(x) (0x00 + (x) * 0x20)
+#define JZ_REG_DMA_DST_ADDR(x) (0x04 + (x) * 0x20)
+#define JZ_REG_DMA_TRANSFER_COUNT(x) (0x08 + (x) * 0x20)
+#define JZ_REG_DMA_REQ_TYPE(x) (0x0C + (x) * 0x20)
+#define JZ_REG_DMA_STATUS_CTRL(x) (0x10 + (x) * 0x20)
+#define JZ_REG_DMA_CMD(x) (0x14 + (x) * 0x20)
+#define JZ_REG_DMA_DESC_ADDR(x) (0x18 + (x) * 0x20)
+
+#define JZ_REG_DMA_CTRL 0x300
+#define JZ_REG_DMA_IRQ 0x304
+#define JZ_REG_DMA_DOORBELL 0x308
+#define JZ_REG_DMA_DOORBELL_SET 0x30C
+
+#define JZ_DMA_STATUS_CTRL_NO_DESC BIT(31)
+#define JZ_DMA_STATUS_CTRL_DESC_INV BIT(6)
+#define JZ_DMA_STATUS_CTRL_ADDR_ERR BIT(4)
+#define JZ_DMA_STATUS_CTRL_TRANSFER_DONE BIT(3)
+#define JZ_DMA_STATUS_CTRL_HALT BIT(2)
+#define JZ_DMA_STATUS_CTRL_COUNT_TERMINATE BIT(1)
+#define JZ_DMA_STATUS_CTRL_ENABLE BIT(0)
+
+#define JZ_DMA_CMD_SRC_INC BIT(23)
+#define JZ_DMA_CMD_DST_INC BIT(22)
+#define JZ_DMA_CMD_RDIL_MASK (0xf << 16)
+#define JZ_DMA_CMD_SRC_WIDTH_MASK (0x3 << 14)
+#define JZ_DMA_CMD_DST_WIDTH_MASK (0x3 << 12)
+#define JZ_DMA_CMD_INTERVAL_LENGTH_MASK (0x7 << 8)
+#define JZ_DMA_CMD_BLOCK_MODE BIT(7)
+#define JZ_DMA_CMD_DESC_VALID BIT(4)
+#define JZ_DMA_CMD_DESC_VALID_MODE BIT(3)
+#define JZ_DMA_CMD_VALID_IRQ_ENABLE BIT(2)
+#define JZ_DMA_CMD_TRANSFER_IRQ_ENABLE BIT(1)
+#define JZ_DMA_CMD_LINK_ENABLE BIT(0)
+
+#define JZ_DMA_CMD_FLAGS_OFFSET 22
+#define JZ_DMA_CMD_RDIL_OFFSET 16
+#define JZ_DMA_CMD_SRC_WIDTH_OFFSET 14
+#define JZ_DMA_CMD_DST_WIDTH_OFFSET 12
+#define JZ_DMA_CMD_TRANSFER_SIZE_OFFSET 8
+#define JZ_DMA_CMD_MODE_OFFSET 7
+
+#define JZ_DMA_CTRL_PRIORITY_MASK (0x3 << 8)
+#define JZ_DMA_CTRL_HALT BIT(3)
+#define JZ_DMA_CTRL_ADDRESS_ERROR BIT(2)
+#define JZ_DMA_CTRL_ENABLE BIT(0)
+
+
+static void __iomem *jz4740_dma_base;
+static spinlock_t jz4740_dma_lock;
+
+static inline uint32_t jz4740_dma_read(size_t reg)
+{
+ return readl(jz4740_dma_base + reg);
+}
+
+static inline void jz4740_dma_write(size_t reg, uint32_t val)
+{
+ writel(val, jz4740_dma_base + reg);
+}
+
+static inline void jz4740_dma_write_mask(size_t reg, uint32_t val, uint32_t mask)
+{
+ uint32_t val2;
+ val2 = jz4740_dma_read(reg);
+ val2 &= ~mask;
+ val2 |= val;
+ jz4740_dma_write(reg, val2);
+}
+
+struct jz4740_dma_chan {
+ unsigned int id;
+ void *dev;
+ const char *name;
+
+ enum jz4740_dma_flags flags;
+ uint32_t transfer_shift;
+
+ jz4740_dma_complete_callback_t complete_cb;
+
+ unsigned used:1;
+};
+
+#define JZ4740_DMA_CHANNEL(_id) { .id = _id }
+
+struct jz4740_dma_chan jz4740_dma_channels[] = {
+ JZ4740_DMA_CHANNEL(0),
+ JZ4740_DMA_CHANNEL(1),
+ JZ4740_DMA_CHANNEL(2),
+ JZ4740_DMA_CHANNEL(3),
+ JZ4740_DMA_CHANNEL(4),
+ JZ4740_DMA_CHANNEL(5),
+};
+
+struct jz4740_dma_chan *jz4740_dma_request(void *dev, const char *name)
+{
+ unsigned int i;
+ struct jz4740_dma_chan *dma = NULL;
+
+ spin_lock(&jz4740_dma_lock);
+
+ for (i = 0; i < ARRAY_SIZE(jz4740_dma_channels); ++i) {
+ if (!jz4740_dma_channels[i].used) {
+ dma = &jz4740_dma_channels[i];
+ dma->used = 1;
+ break;
+ }
+ }
+
+ spin_unlock(&jz4740_dma_lock);
+
+ if (!dma)
+ return NULL;
+
+ dma->dev = dev;
+ dma->name = name;
+
+ return dma;
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_request);
+
+void jz4740_dma_configure(struct jz4740_dma_chan *dma,
+ const struct jz4740_dma_config *config)
+{
+ uint32_t cmd;
+
+ switch (config->transfer_size) {
+ case JZ4740_DMA_TRANSFER_SIZE_2BYTE:
+ dma->transfer_shift = 1;
+ break;
+ case JZ4740_DMA_TRANSFER_SIZE_4BYTE:
+ dma->transfer_shift = 2;
+ break;
+ case JZ4740_DMA_TRANSFER_SIZE_16BYTE:
+ dma->transfer_shift = 4;
+ break;
+ case JZ4740_DMA_TRANSFER_SIZE_32BYTE:
+ dma->transfer_shift = 5;
+ break;
+ default:
+ dma->transfer_shift = 0;
+ break;
+ }
+
+ cmd = config->flags << JZ_DMA_CMD_FLAGS_OFFSET;
+ cmd |= config->src_width << JZ_DMA_CMD_SRC_WIDTH_OFFSET;
+ cmd |= config->dst_width << JZ_DMA_CMD_DST_WIDTH_OFFSET;
+ cmd |= config->transfer_size << JZ_DMA_CMD_TRANSFER_SIZE_OFFSET;
+ cmd |= config->mode << JZ_DMA_CMD_MODE_OFFSET;
+ cmd |= JZ_DMA_CMD_TRANSFER_IRQ_ENABLE;
+
+ jz4740_dma_write(JZ_REG_DMA_CMD(dma->id), cmd);
+ jz4740_dma_write(JZ_REG_DMA_STATUS_CTRL(dma->id), 0);
+ jz4740_dma_write(JZ_REG_DMA_REQ_TYPE(dma->id), config->request_type);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_configure);
+
+void jz4740_dma_set_src_addr(struct jz4740_dma_chan *dma, dma_addr_t src)
+{
+ jz4740_dma_write(JZ_REG_DMA_SRC_ADDR(dma->id), src);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_set_src_addr);
+
+void jz4740_dma_set_dst_addr(struct jz4740_dma_chan *dma, dma_addr_t dst)
+{
+ jz4740_dma_write(JZ_REG_DMA_DST_ADDR(dma->id), dst);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_set_dst_addr);
+
+void jz4740_dma_set_transfer_count(struct jz4740_dma_chan *dma, uint32_t count)
+{
+ count >>= dma->transfer_shift;
+ jz4740_dma_write(JZ_REG_DMA_TRANSFER_COUNT(dma->id), count);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_set_transfer_count);
+
+void jz4740_dma_set_complete_cb(struct jz4740_dma_chan *dma,
+ jz4740_dma_complete_callback_t cb)
+{
+ dma->complete_cb = cb;
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_set_complete_cb);
+
+void jz4740_dma_free(struct jz4740_dma_chan *dma)
+{
+ dma->dev = NULL;
+ dma->complete_cb = NULL;
+ dma->used = 0;
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_free);
+
+void jz4740_dma_enable(struct jz4740_dma_chan *dma)
+{
+ jz4740_dma_write_mask(JZ_REG_DMA_STATUS_CTRL(dma->id),
+ JZ_DMA_STATUS_CTRL_NO_DESC | JZ_DMA_STATUS_CTRL_ENABLE,
+ JZ_DMA_STATUS_CTRL_HALT | JZ_DMA_STATUS_CTRL_NO_DESC |
+ JZ_DMA_STATUS_CTRL_ENABLE);
+
+ jz4740_dma_write_mask(JZ_REG_DMA_CTRL,
+ JZ_DMA_CTRL_ENABLE,
+ JZ_DMA_CTRL_HALT | JZ_DMA_CTRL_ENABLE);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_enable);
+
+void jz4740_dma_disable(struct jz4740_dma_chan *dma)
+{
+ jz4740_dma_write_mask(JZ_REG_DMA_STATUS_CTRL(dma->id), 0,
+ JZ_DMA_STATUS_CTRL_ENABLE);
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_disable);
+
+uint32_t jz4740_dma_get_residue(const struct jz4740_dma_chan *dma)
+{
+ uint32_t residue;
+ residue = jz4740_dma_read(JZ_REG_DMA_TRANSFER_COUNT(dma->id));
+ return residue << dma->transfer_shift;
+}
+EXPORT_SYMBOL_GPL(jz4740_dma_get_residue);
+
+static void jz4740_dma_chan_irq(struct jz4740_dma_chan *dma)
+{
+ uint32_t status;
+
+ status = jz4740_dma_read(JZ_REG_DMA_STATUS_CTRL(dma->id));
+
+ jz4740_dma_write_mask(JZ_REG_DMA_STATUS_CTRL(dma->id), 0,
+ JZ_DMA_STATUS_CTRL_ENABLE | JZ_DMA_STATUS_CTRL_TRANSFER_DONE);
+
+ if (dma->complete_cb)
+ dma->complete_cb(dma, 0, dma->dev);
+}
+
+static irqreturn_t jz4740_dma_irq(int irq, void *dev_id)
+{
+ uint32_t irq_status;
+ unsigned int i;
+
+ irq_status = readl(jz4740_dma_base + JZ_REG_DMA_IRQ);
+
+ for (i = 0; i < 6; ++i) {
+ if (irq_status & (1 << i))
+ jz4740_dma_chan_irq(&jz4740_dma_channels[i]);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int jz4740_dma_init(void)
+{
+ unsigned int ret;
+
+ jz4740_dma_base = ioremap(JZ4740_DMAC_BASE_ADDR, 0x400);
+
+ if (!jz4740_dma_base)
+ return -EBUSY;
+
+ spin_lock_init(&jz4740_dma_lock);
+
+ ret = request_irq(JZ4740_IRQ_DMAC, jz4740_dma_irq, 0, "DMA", NULL);
+
+ if (ret)
+ printk(KERN_ERR "JZ4740 DMA: Failed to request irq: %d\n", ret);
+
+ return ret;
+}
+arch_initcall(jz4740_dma_init);