| /* |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * 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/io.h> |
| #include <linux/of.h> |
| #include <linux/printk.h> |
| #include <linux/slab.h> |
| #include <linux/types.h> |
| #include <asm/bmips.h> |
| |
| /* |
| * 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 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. |
| */ |
| |
| struct bmips_dma_range { |
| u32 child_addr; |
| u32 parent_addr; |
| u32 size; |
| }; |
| |
| static struct bmips_dma_range *bmips_dma_ranges; |
| |
| #define FLUSH_RAC 0x100 |
| |
| dma_addr_t phys_to_dma(struct device *dev, phys_addr_t pa) |
| { |
| 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; |
| } |
| |
| phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr) |
| { |
| 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; |
| } |
| |
| void arch_sync_dma_for_cpu_all(void) |
| { |
| void __iomem *cbr = BMIPS_GET_CBR(); |
| u32 cfg; |
| |
| if (boot_cpu_type() != CPU_BMIPS3300 && |
| boot_cpu_type() != CPU_BMIPS4350 && |
| boot_cpu_type() != CPU_BMIPS4380) |
| return; |
| |
| /* Flush stale data out of the readahead cache */ |
| cfg = __raw_readl(cbr + BMIPS_RAC_CONFIG); |
| __raw_writel(cfg | 0x100, cbr + BMIPS_RAC_CONFIG); |
| __raw_readl(cbr + BMIPS_RAC_CONFIG); |
| } |
| |
| static int __init bmips_init_dma_ranges(void) |
| { |
| 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; |
| |
| 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 = kcalloc(len + 1, sizeof(struct bmips_dma_range), |
| 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(bmips_init_dma_ranges); |