[PATCH] arm64: kexec: set asdie firmware-reserved memory regions

[AKASHI Takahiro]

Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
---
 arch/arm64/kernel/setup.c | 24 ++++++++++++++++++++----
 arch/arm64/mm/init.c      | 21 +++++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 30ad2f085d1f..997f07e86243 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -87,6 +87,9 @@ static struct resource mem_res[] = {
 #define kernel_code mem_res[0]
 #define kernel_data mem_res[1]
 
+/* TODO: Firmware-reserved memory resources */
+extern struct memblock_type fw_mem;
+
 /*
  * The recorded values of x0 .. x3 upon kernel entry.
  */
@@ -206,7 +209,20 @@ static void __init request_standard_resources(void)
 {
 	struct memblock_region *region;
 	struct resource *res;
+	int i;
+
+	/* add firmware-reserved memory first */
+	for (i = 1; i < fw_mem.cnt; i++) {
+		res = alloc_bootmem_low(sizeof(*res));
+		res->name  = "reserved";
+		res->flags = IORESOURCE_MEM;
+		res->start = fw_mem.regions[i].base;
+		res->end = fw_mem.regions[i].base + fw_mem.regions[i].size - 1;
 
+		request_resource(&iomem_resource, res);
+	}
+
+	/* add standard resources */
 	kernel_code.start   = __pa_symbol(_text);
 	kernel_code.end     = __pa_symbol(__init_begin - 1);
 	kernel_data.start   = __pa_symbol(_sdata);
@@ -224,19 +240,19 @@ static void __init request_standard_resources(void)
 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 
-		request_resource(&iomem_resource, res);
+		insert_resource(&iomem_resource, res);
 
 		if (kernel_code.start >= res->start &&
 		    kernel_code.end <= res->end)
-			request_resource(res, &kernel_code);
+			insert_resource(res, &kernel_code);
 		if (kernel_data.start >= res->start &&
 		    kernel_data.end <= res->end)
-			request_resource(res, &kernel_data);
+			insert_resource(res, &kernel_data);
 #ifdef CONFIG_KEXEC_CORE
 		/* Userspace will find "Crash kernel" region in /proc/iomem. */
 		if (crashk_res.end && crashk_res.start >= res->start &&
 		    crashk_res.end <= res->end)
-			request_resource(res, &crashk_res);
+			insert_resource(res, &crashk_res);
 #endif
 	}
 }
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 9f3c47acf8ff..b6f86a7bbfb7 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -62,6 +62,14 @@
 s64 memstart_addr __ro_after_init = -1;
 phys_addr_t arm64_dma_phys_limit __ro_after_init;
 
+static struct memblock_region fw_mem_regions[INIT_MEMBLOCK_REGIONS];
+struct memblock_type fw_mem = {
+	.regions	= fw_mem_regions,
+	.cnt		= 1,    /* empty dummy entry */
+	.max		= INIT_MEMBLOCK_REGIONS,
+	.name		= "firmware-reserved memory",
+};
+
 #ifdef CONFIG_BLK_DEV_INITRD
 static int __init early_initrd(char *p)
 {
@@ -362,6 +370,19 @@ static void __init fdt_enforce_memory_region(void)
 void __init arm64_memblock_init(void)
 {
 	const s64 linear_region_size = -(s64)PAGE_OFFSET;
+	struct memblock_region *region;
+
+	/*
+	 * Export firmware-reserved memory regions
+	 * TODO: via more generic interface
+	 */
+	for_each_memblock(reserved, region) {
+		if (WARN_ON(fw_mem.cnt >= fw_mem.max))
+			break;
+		fw_mem.regions[fw_mem.cnt].base = region->base;
+		fw_mem.regions[fw_mem.cnt].size = region->size;
+		fw_mem.cnt++;
+	}
 
 	/* Handle linux,usable-memory-range property */
 	fdt_enforce_memory_region();
-- 
2.16.2