mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
[AVR32] Reserve framebuffer memory in early_parse_fbmem()
With the current strategy of using the bootmem allocator to allocate or reserve framebuffer memory, there's a slight chance that the requested area has been taken by the boot allocator bitmap before we get around to reserving it. By inserting the framebuffer region as a reserved region as early as possible, we improve our chances for success and we make the region visible as a reserved region in dmesg and /proc/iomem without any extra work. Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
This commit is contained in:
parent
d8011768e6
commit
f9692b9501
1 changed files with 61 additions and 7 deletions
|
@ -191,21 +191,45 @@ find_free_region(const struct resource *mem, resource_size_t size,
|
|||
return target;
|
||||
}
|
||||
|
||||
static int __init
|
||||
alloc_reserved_region(resource_size_t *start, resource_size_t size,
|
||||
resource_size_t align, const char *name)
|
||||
{
|
||||
struct resource *mem;
|
||||
resource_size_t target;
|
||||
int ret;
|
||||
|
||||
for (mem = system_ram; mem; mem = mem->sibling) {
|
||||
target = find_free_region(mem, size, align);
|
||||
if (target <= mem->end) {
|
||||
ret = add_reserved_region(target, target + size - 1,
|
||||
name);
|
||||
if (!ret)
|
||||
*start = target;
|
||||
return ret;
|
||||
}
|
||||
}
|
||||
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
/*
|
||||
* Early framebuffer allocation. Works as follows:
|
||||
* - If fbmem_size is zero, nothing will be allocated or reserved.
|
||||
* - If fbmem_start is zero when setup_bootmem() is called,
|
||||
* fbmem_size bytes will be allocated from the bootmem allocator.
|
||||
* a block of fbmem_size bytes will be reserved before bootmem
|
||||
* initialization. It will be aligned to the largest page size
|
||||
* that fbmem_size is a multiple of.
|
||||
* - If fbmem_start is nonzero, an area of size fbmem_size will be
|
||||
* reserved at the physical address fbmem_start if necessary. If
|
||||
* the area isn't in a memory region known to the kernel, it will
|
||||
* be left alone.
|
||||
* reserved at the physical address fbmem_start if possible. If
|
||||
* it collides with other reserved memory, a different block of
|
||||
* same size will be allocated, just as if fbmem_start was zero.
|
||||
*
|
||||
* Board-specific code may use these variables to set up platform data
|
||||
* for the framebuffer driver if fbmem_size is nonzero.
|
||||
*/
|
||||
static unsigned long __initdata fbmem_start;
|
||||
static unsigned long __initdata fbmem_size;
|
||||
static resource_size_t __initdata fbmem_start;
|
||||
static resource_size_t __initdata fbmem_size;
|
||||
|
||||
/*
|
||||
* "fbmem=xxx[kKmM]" allocates the specified amount of boot memory for
|
||||
|
@ -219,9 +243,39 @@ static unsigned long __initdata fbmem_size;
|
|||
*/
|
||||
static int __init early_parse_fbmem(char *p)
|
||||
{
|
||||
int ret;
|
||||
unsigned long align;
|
||||
|
||||
fbmem_size = memparse(p, &p);
|
||||
if (*p == '@')
|
||||
if (*p == '@') {
|
||||
fbmem_start = memparse(p, &p);
|
||||
ret = add_reserved_region(fbmem_start,
|
||||
fbmem_start + fbmem_size - 1,
|
||||
"Framebuffer");
|
||||
if (ret) {
|
||||
printk(KERN_WARNING
|
||||
"Failed to reserve framebuffer memory\n");
|
||||
fbmem_start = 0;
|
||||
}
|
||||
}
|
||||
|
||||
if (!fbmem_start) {
|
||||
if ((fbmem_size & 0x000fffffUL) == 0)
|
||||
align = 0x100000; /* 1 MiB */
|
||||
else if ((fbmem_size & 0x0000ffffUL) == 0)
|
||||
align = 0x10000; /* 64 KiB */
|
||||
else
|
||||
align = 0x1000; /* 4 KiB */
|
||||
|
||||
ret = alloc_reserved_region(&fbmem_start, fbmem_size,
|
||||
align, "Framebuffer");
|
||||
if (ret) {
|
||||
printk(KERN_WARNING
|
||||
"Failed to allocate framebuffer memory\n");
|
||||
fbmem_size = 0;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
early_param("fbmem", early_parse_fbmem);
|
||||
|
|
Loading…
Reference in a new issue