powerpc: introduce early_get_first_memblock_info

For a relocatable kernel since it can be loaded at any place, there
is no any relation between the kernel start addr and the memstart_addr.
So we can't calculate the memstart_addr from kernel start addr. And
also we can't wait to do the relocation after we get the real
memstart_addr from device tree because it is so late. So introduce
a new function we can use to get the first memblock address and size
in a very early stage (before machine_init).

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit is contained in:
Kevin Hao 2013-12-24 15:12:08 +08:00 committed by Scott Wood
parent 78a235efdc
commit b27652dd21
2 changed files with 41 additions and 1 deletions

View File

@ -523,6 +523,20 @@ static int __init early_init_dt_scan_memory_ppc(unsigned long node,
return early_init_dt_scan_memory(node, uname, depth, data);
}
/*
* For a relocatable kernel, we need to get the memstart_addr first,
* then use it to calculate the virtual kernel start address. This has
* to happen at a very early stage (before machine_init). In this case,
* we just want to get the memstart_address and would not like to mess the
* memblock at this stage. So introduce a variable to skip the memblock_add()
* for this reason.
*/
#ifdef CONFIG_RELOCATABLE
static int add_mem_to_memblock = 1;
#else
#define add_mem_to_memblock 1
#endif
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
#ifdef CONFIG_PPC64
@ -543,7 +557,8 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
}
/* Add the chunk to the MEMBLOCK list */
memblock_add(base, size);
if (add_mem_to_memblock)
memblock_add(base, size);
}
static void __init early_reserve_mem_dt(void)
@ -740,6 +755,30 @@ void __init early_init_devtree(void *params)
DBG(" <- early_init_devtree()\n");
}
#ifdef CONFIG_RELOCATABLE
/*
* This function run before early_init_devtree, so we have to init
* initial_boot_params.
*/
void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
{
/* Setup flat device-tree pointer */
initial_boot_params = params;
/*
* Scan the memory nodes and set add_mem_to_memblock to 0 to avoid
* mess the memblock.
*/
add_mem_to_memblock = 0;
of_scan_flat_dt(early_init_dt_scan_root, NULL);
of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
add_mem_to_memblock = 1;
if (size)
*size = first_memblock_size;
}
#endif
/*******
*
* New implementation of the OF "find" APIs, return a refcounted

View File

@ -116,6 +116,7 @@ extern const void *of_flat_dt_match_machine(const void *default_match,
extern void unflatten_device_tree(void);
extern void unflatten_and_copy_device_tree(void);
extern void early_init_devtree(void *);
extern void early_get_first_memblock_info(void *, phys_addr_t *);
#else /* CONFIG_OF_FLATTREE */
static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
static inline void unflatten_device_tree(void) {}