124 lines
3.0 KiB
C
124 lines
3.0 KiB
C
/*
|
|
* 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);
|