msm: 8974: Add function to reserve memory from device tree
Memory reservations for memory pools or using memblock remove
must happen early at bootup. Add a function at early boot to
walk the flattened device tree and extract memory reservation
information from appropriate bindings in device tree. To ensure
that the memory is only reserved when a driver is enabled,
drivers must put EXPORT_COMPAT(<compat string>) in the driver
as well as adding the binding to the device tree. More
documentation is available in
Documentation/devicetree/bindings/arm/msm/memory-reserve.txt
Change-Id: I28fa71d7a30cea9af5447acb5d2dde562fa0f6de
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/arch/arm/mach-msm/memory.c b/arch/arm/mach-msm/memory.c
index a1b21c5..63c2d3a 100644
--- a/arch/arm/mach-msm/memory.c
+++ b/arch/arm/mach-msm/memory.c
@@ -37,6 +37,7 @@
#include <mach/msm_iomap.h>
#include <mach/socinfo.h>
#include <linux/sched.h>
+#include <linux/of_fdt.h>
/* fixme */
#include <asm/tlbflush.h>
@@ -381,3 +382,117 @@
{
return fmem_set_state(FMEM_T_STATE);
}
+
+static char * const memtype_names[] = {
+ [MEMTYPE_SMI_KERNEL] = "SMI_KERNEL",
+ [MEMTYPE_SMI] = "SMI",
+ [MEMTYPE_EBI0] = "EBI0",
+ [MEMTYPE_EBI1] = "EBI1",
+};
+
+static int reserve_memory_type(char *mem_name,
+ struct memtype_reserve *reserve_table,
+ int size)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(memtype_names); i++) {
+ if (memtype_names[i] && strcmp(mem_name,
+ memtype_names[i]) == 0) {
+ reserve_table[i].size += size;
+ return 0;
+ }
+ }
+
+ pr_err("Could not find memory type %s\n", mem_name);
+ return -EINVAL;
+}
+
+static int check_for_compat(unsigned long node)
+{
+ char **start = __compat_exports_start;
+
+ for ( ; start < __compat_exports_end; start++)
+ if (of_flat_dt_is_compatible(node, *start))
+ return 1;
+
+ return 0;
+}
+
+int __init dt_scan_for_memory_reserve(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ char *memory_name_prop;
+ unsigned int *memory_remove_prop;
+ unsigned long memory_name_prop_length;
+ unsigned long memory_remove_prop_length;
+ unsigned long memory_size_prop_length;
+ unsigned int *memory_size_prop;
+ unsigned int memory_size;
+ unsigned int memory_start;
+ int ret;
+
+ memory_name_prop = of_get_flat_dt_prop(node,
+ "qcom,memory-reservation-type",
+ &memory_name_prop_length);
+ memory_remove_prop = of_get_flat_dt_prop(node,
+ "qcom,memblock-remove",
+ &memory_remove_prop_length);
+
+ if (memory_name_prop || memory_remove_prop) {
+ if (!check_for_compat(node))
+ goto out;
+ } else {
+ goto out;
+ }
+
+ if (memory_name_prop) {
+ if (strnlen(memory_name_prop, memory_name_prop_length) == 0) {
+ WARN(1, "Memory name was malformed\n");
+ goto mem_remove;
+ }
+
+ memory_size_prop = of_get_flat_dt_prop(node,
+ "qcom,memory-reservation-size",
+ &memory_size_prop_length);
+
+ if (memory_size_prop &&
+ (memory_size_prop_length == sizeof(unsigned int))) {
+ memory_size = be32_to_cpu(*memory_size_prop);
+
+ if (reserve_memory_type(memory_name_prop,
+ data, memory_size) == 0)
+ pr_info("%s reserved %s size %x\n",
+ uname, memory_name_prop, memory_size);
+ else
+ WARN(1, "Node %s reserve failed\n",
+ uname);
+ } else {
+ WARN(1, "Node %s specified bad/nonexistent size\n",
+ uname);
+ }
+ }
+
+mem_remove:
+
+ if (memory_remove_prop) {
+ if (memory_remove_prop_length != (2*sizeof(unsigned int))) {
+ WARN(1, "Memory remove malformed\n");
+ goto out;
+ }
+
+ memory_start = be32_to_cpu(memory_remove_prop[0]);
+ memory_size = be32_to_cpu(memory_remove_prop[1]);
+
+ ret = memblock_remove(memory_start, memory_size);
+ if (ret)
+ WARN(1, "Failed to remove memory %x-%x\n",
+ memory_start, memory_start+memory_size);
+ else
+ pr_info("Node %s removed memory %x-%x\n", uname,
+ memory_start, memory_start+memory_size);
+ }
+
+out:
+ return 0;
+}