diff options
Diffstat (limited to 'arch/mips/bmips')
| -rw-r--r-- | arch/mips/bmips/dma.c | 100 |
1 files changed, 68 insertions, 32 deletions
diff --git a/arch/mips/bmips/dma.c b/arch/mips/bmips/dma.c index ea42012fd4f5..04790f4e1805 100644 --- a/arch/mips/bmips/dma.c +++ b/arch/mips/bmips/dma.c @@ -6,76 +6,112 @@ * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com> */ +#define pr_fmt(fmt) "bmips-dma: " fmt + #include <linux/device.h> #include <linux/dma-direction.h> #include <linux/dma-mapping.h> #include <linux/init.h> -#include <linux/mm.h> +#include <linux/io.h> #include <linux/of.h> -#include <linux/pci.h> +#include <linux/printk.h> +#include <linux/slab.h> #include <linux/types.h> #include <dma-coherence.h> /* - * BCM3384 has configurable address translation windows which allow the + * BCM338x has configurable address translation windows which allow the * peripherals' DMA addresses to be different from the Zephyr-visible * physical addresses. e.g. usb_dma_addr = zephyr_pa ^ 0x08000000 * - * If our DT "memory" node has a "dma-xor-mask" property we will enable this - * translation using the provided offset. + * If the "brcm,ubus" node has a "dma-ranges" property we will enable this + * translation globally using the provided information. This implements a + * very limited subset of "dma-ranges" support and it will probably be + * replaced by a more generic version later. */ -static u32 bcm3384_dma_xor_mask; -static u32 bcm3384_dma_xor_limit = 0xffffffff; -/* - * PCI collapses the memory hole at 0x10000000 - 0x1fffffff. - * On systems with a dma-xor-mask, this range is guaranteed to live above - * the dma-xor-limit. - */ -#define BCM3384_MEM_HOLE_PA 0x10000000 -#define BCM3384_MEM_HOLE_SIZE 0x10000000 +struct bmips_dma_range { + u32 child_addr; + u32 parent_addr; + u32 size; +}; -static dma_addr_t bcm3384_phys_to_dma(struct device *dev, phys_addr_t pa) +static struct bmips_dma_range *bmips_dma_ranges; + +#define FLUSH_RAC 0x100 + +static dma_addr_t bmips_phys_to_dma(struct device *dev, phys_addr_t pa) { - if (dev && dev_is_pci(dev) && - pa >= (BCM3384_MEM_HOLE_PA + BCM3384_MEM_HOLE_SIZE)) - return pa - BCM3384_MEM_HOLE_SIZE; - if (pa <= bcm3384_dma_xor_limit) - return pa ^ bcm3384_dma_xor_mask; + struct bmips_dma_range *r; + + for (r = bmips_dma_ranges; r && r->size; r++) { + if (pa >= r->child_addr && + pa < (r->child_addr + r->size)) + return pa - r->child_addr + r->parent_addr; + } return pa; } dma_addr_t plat_map_dma_mem(struct device *dev, void *addr, size_t size) { - return bcm3384_phys_to_dma(dev, virt_to_phys(addr)); + return bmips_phys_to_dma(dev, virt_to_phys(addr)); } dma_addr_t plat_map_dma_mem_page(struct device *dev, struct page *page) { - return bcm3384_phys_to_dma(dev, page_to_phys(page)); + return bmips_phys_to_dma(dev, page_to_phys(page)); } unsigned long plat_dma_addr_to_phys(struct device *dev, dma_addr_t dma_addr) { - if (dev && dev_is_pci(dev) && - dma_addr >= BCM3384_MEM_HOLE_PA) - return dma_addr + BCM3384_MEM_HOLE_SIZE; - if ((dma_addr ^ bcm3384_dma_xor_mask) <= bcm3384_dma_xor_limit) - return dma_addr ^ bcm3384_dma_xor_mask; + struct bmips_dma_range *r; + + for (r = bmips_dma_ranges; r && r->size; r++) { + if (dma_addr >= r->parent_addr && + dma_addr < (r->parent_addr + r->size)) + return dma_addr - r->parent_addr + r->child_addr; + } return dma_addr; } -static int __init bcm3384_init_dma_xor(void) +static int __init bmips_init_dma_ranges(void) { - struct device_node *np = of_find_node_by_type(NULL, "memory"); + struct device_node *np = + of_find_compatible_node(NULL, NULL, "brcm,ubus"); + const __be32 *data; + struct bmips_dma_range *r; + int len; if (!np) return 0; - of_property_read_u32(np, "dma-xor-mask", &bcm3384_dma_xor_mask); - of_property_read_u32(np, "dma-xor-limit", &bcm3384_dma_xor_limit); + data = of_get_property(np, "dma-ranges", &len); + if (!data) + goto out_good; + + len /= sizeof(*data) * 3; + if (!len) + goto out_bad; + + /* add a dummy (zero) entry at the end as a sentinel */ + bmips_dma_ranges = kzalloc(sizeof(struct bmips_dma_range) * (len + 1), + GFP_KERNEL); + if (!bmips_dma_ranges) + goto out_bad; + for (r = bmips_dma_ranges; len; len--, r++) { + r->child_addr = be32_to_cpup(data++); + r->parent_addr = be32_to_cpup(data++); + r->size = be32_to_cpup(data++); + } + +out_good: of_node_put(np); return 0; + +out_bad: + pr_err("error parsing dma-ranges property\n"); + of_node_put(np); + return -EINVAL; } -arch_initcall(bcm3384_init_dma_xor); +arch_initcall(bmips_init_dma_ranges); |