Export the DMA register information from the SoC specific data, such that we can access the registers directly in omap-dma.c, mapping the register region ourselves as well.
Rather than calculating the DMA channel register in its entirety for each access, we pre-calculate an offset base address for the allocated DMA channel and then just use the appropriate register offset. Signed-off-by: Russell King <[email protected]> --- arch/arm/mach-omap1/dma.c | 2 + arch/arm/mach-omap2/dma.c | 2 + drivers/dma/omap-dma.c | 96 ++++++++++++++++++++++++++++++++++++++++---- include/linux/omap-dma.h | 2 + 4 files changed, 93 insertions(+), 9 deletions(-) diff --git a/arch/arm/mach-omap1/dma.c b/arch/arm/mach-omap1/dma.c index 8b1b914d0a6f..3afde9628839 100644 --- a/arch/arm/mach-omap1/dma.c +++ b/arch/arm/mach-omap1/dma.c @@ -264,6 +264,8 @@ static const struct platform_device_info omap_dma_dev_info = { }; static struct omap_system_dma_plat_info dma_plat_info __initdata = { + .reg_map = reg_map, + .channel_stride = 0x40, .show_dma_caps = omap1_show_dma_caps, .clear_lch_regs = omap1_clear_lch_regs, .clear_dma = omap1_clear_dma, diff --git a/arch/arm/mach-omap2/dma.c b/arch/arm/mach-omap2/dma.c index 6331fc4b4054..e08e55a173b6 100644 --- a/arch/arm/mach-omap2/dma.c +++ b/arch/arm/mach-omap2/dma.c @@ -205,6 +205,8 @@ static unsigned configure_dma_errata(void) } static struct omap_system_dma_plat_info dma_plat_info __initdata = { + .reg_map = reg_map, + .channel_stride = 0x60, .show_dma_caps = omap2_show_dma_caps, .clear_dma = omap2_clear_dma, .dma_write = dma_write, diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 04631e6732c4..611963e82623 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -27,13 +27,16 @@ struct omap_dmadev { spinlock_t lock; struct tasklet_struct task; struct list_head pending; + void __iomem *base; + const struct omap_dma_reg *reg_map; struct omap_system_dma_plat_info *plat; }; struct omap_chan { struct virt_dma_chan vc; struct list_head node; - struct omap_system_dma_plat_info *plat; + void __iomem *channel_base; + const struct omap_dma_reg *reg_map; struct dma_slave_config cfg; unsigned dma_sig; @@ -169,24 +172,77 @@ static void omap_dma_desc_free(struct virt_dma_desc *vd) kfree(container_of(vd, struct omap_desc, vd)); } +static void omap_dma_write(uint32_t val, unsigned type, void __iomem *addr) +{ + switch (type) { + case OMAP_DMA_REG_16BIT: + writew_relaxed(val, addr); + break; + case OMAP_DMA_REG_2X16BIT: + writew_relaxed(val, addr); + writew_relaxed(val >> 16, addr + 2); + break; + case OMAP_DMA_REG_32BIT: + writel_relaxed(val, addr); + break; + default: + WARN_ON(1); + } +} + +static unsigned omap_dma_read(unsigned type, void __iomem *addr) +{ + unsigned val; + + switch (type) { + case OMAP_DMA_REG_16BIT: + val = readw_relaxed(addr); + break; + case OMAP_DMA_REG_2X16BIT: + val = readw_relaxed(addr); + val |= readw_relaxed(addr + 2) << 16; + break; + case OMAP_DMA_REG_32BIT: + val = readl_relaxed(addr); + break; + default: + WARN_ON(1); + val = 0; + } + + return val; +} + static void omap_dma_glbl_write(struct omap_dmadev *od, unsigned reg, unsigned val) { - od->plat->dma_write(val, reg, 0); + const struct omap_dma_reg *r = od->reg_map + reg; + + WARN_ON(r->stride); + + omap_dma_write(val, r->type, od->base + r->offset); } static unsigned omap_dma_glbl_read(struct omap_dmadev *od, unsigned reg) { - return od->plat->dma_read(reg, 0); + const struct omap_dma_reg *r = od->reg_map + reg; + + WARN_ON(r->stride); + + return omap_dma_read(r->type, od->base + r->offset); } static void omap_dma_chan_write(struct omap_chan *c, unsigned reg, unsigned val) { - c->plat->dma_write(val, reg, c->dma_ch); + const struct omap_dma_reg *r = c->reg_map + reg; + + omap_dma_write(val, r->type, c->channel_base + r->offset); } static unsigned omap_dma_chan_read(struct omap_chan *c, unsigned reg) { - return c->plat->dma_read(reg, c->dma_ch); + const struct omap_dma_reg *r = c->reg_map + reg; + + return omap_dma_read(r->type, c->channel_base + r->offset); } static void omap_dma_clear_csr(struct omap_chan *c) @@ -197,6 +253,12 @@ static void omap_dma_clear_csr(struct omap_chan *c) omap_dma_chan_write(c, CSR, ~0); } +static void omap_dma_assign(struct omap_dmadev *od, struct omap_chan *c, + unsigned lch) +{ + c->channel_base = od->base + od->plat->channel_stride * lch; +} + static void omap_dma_start(struct omap_chan *c, struct omap_desc *d) { struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device); @@ -400,18 +462,26 @@ static void omap_dma_sched(unsigned long data) static int omap_dma_alloc_chan_resources(struct dma_chan *chan) { + struct omap_dmadev *od = to_omap_dma_dev(chan->device); struct omap_chan *c = to_omap_dma_chan(chan); + int ret; + + dev_info(od->ddev.dev, "allocating channel for %u\n", c->dma_sig); - dev_info(c->vc.chan.device->dev, "allocating channel for %u\n", c->dma_sig); + ret = omap_request_dma(c->dma_sig, "DMA engine", omap_dma_callback, + c, &c->dma_ch); - return omap_request_dma(c->dma_sig, "DMA engine", - omap_dma_callback, c, &c->dma_ch); + if (ret >= 0) + omap_dma_assign(od, c, c->dma_ch); + + return ret; } static void omap_dma_free_chan_resources(struct dma_chan *chan) { struct omap_chan *c = to_omap_dma_chan(chan); + c->channel_base = NULL; vchan_free_chan_resources(&c->vc); omap_free_dma(c->dma_ch); @@ -901,7 +971,7 @@ static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig) if (!c) return -ENOMEM; - c->plat = od->plat; + c->reg_map = od->reg_map; c->dma_sig = dma_sig; c->vc.desc_free = omap_dma_desc_free; vchan_init(&c->vc, &od->ddev); @@ -928,16 +998,24 @@ static void omap_dma_free(struct omap_dmadev *od) static int omap_dma_probe(struct platform_device *pdev) { struct omap_dmadev *od; + struct resource *res; int rc, i; od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL); if (!od) return -ENOMEM; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + od->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(od->base)) + return PTR_ERR(od->base); + od->plat = omap_get_plat_info(); if (!od->plat) return -EPROBE_DEFER; + od->reg_map = od->plat->reg_map; + dma_cap_set(DMA_SLAVE, od->ddev.cap_mask); dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask); od->ddev.device_alloc_chan_resources = omap_dma_alloc_chan_resources; diff --git a/include/linux/omap-dma.h b/include/linux/omap-dma.h index 7813636a193d..41a13e70f41f 100644 --- a/include/linux/omap-dma.h +++ b/include/linux/omap-dma.h @@ -285,6 +285,8 @@ struct omap_dma_reg { /* System DMA platform data structure */ struct omap_system_dma_plat_info { + const struct omap_dma_reg *reg_map; + unsigned channel_stride; struct omap_dma_dev_attr *dma_attr; u32 errata; void (*show_dma_caps)(void); -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
