diff options
Diffstat (limited to 'arch/mips/jz4740/dma.c')
| -rw-r--r-- | arch/mips/jz4740/dma.c | 289 |
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 000000000000..5ebe75a68350 --- /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); |