From d4ff9c40baf3cf64565c423d6f7622f27ec48a84 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Wed, 14 Mar 2018 16:14:02 +0100 Subject: common: Add functions to find free RAM The bootm code needs to put the Kernel image and initrd into free RAM. Add some functions to find free RAM chunks to help this code. Signed-off-by: Sascha Hauer --- common/memory.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'common/memory.c') diff --git a/common/memory.c b/common/memory.c index ff5bdc14e2..00fa7c50ff 100644 --- a/common/memory.c +++ b/common/memory.c @@ -171,6 +171,57 @@ int release_sdram_region(struct resource *res) return release_region(res); } +void memory_bank_find_space(struct memory_bank *bank, resource_size_t *retstart, + resource_size_t *retend) +{ + resource_size_t freeptr, size, maxfree = 0; + struct resource *last, *child; + + if (list_empty(&bank->res->children)) { + /* No children - return the whole bank */ + *retstart = bank->res->start; + *retend = bank->res->end; + return; + } + + freeptr = bank->res->start; + + list_for_each_entry(child, &bank->res->children, sibling) { + /* Check gaps between child resources */ + size = child->start - freeptr; + if (size > maxfree) { + *retstart = freeptr; + *retend = child->start - 1; + maxfree = size; + } + freeptr = child->start + resource_size(child); + } + + last = list_last_entry(&bank->res->children, struct resource, sibling); + + /* Check gap between last child and end of memory bank */ + freeptr = last->start + resource_size(last); + size = bank->res->start + resource_size(bank->res) - freeptr; + + if (size > maxfree) { + *retstart = freeptr; + *retend = bank->res->end; + } +} + +int memory_bank_first_find_space(resource_size_t *retstart, + resource_size_t *retend) +{ + struct memory_bank *bank; + + for_each_memory_bank(bank) { + memory_bank_find_space(bank, retstart, retend); + return 0; + } + + return -ENOENT; +} + #ifdef CONFIG_OFTREE static int of_memory_fixup(struct device_node *node, void *unused) -- cgit v1.2.3