cpu/amd: Detect any conflicts between sysinfo and the stack region

When increasing the number of supported CPUs on AMD Family 10h/15h
systems there is a relatively high chance of causing a collision
between the CAR global variable region and the AP stack space.
Such collision was noted when increasing the number of supported
CPUs to 32 on the ASUS KGPE-D16.

Detect collision at runtime and print a warning if collision is
present.

Change-Id: Ib5c32f868b1dfffb3b840bb1b1df5f55b5a25f8d
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: http://review.coreboot.org/10401
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>

9 files changed, 64 insertions, 1 deletions

diff --git a/src/cpu/Kconfig b/src/cpu/Kconfig
index c8dc136d38..ae2e88c7d4 100644
--- a/src/cpu/Kconfig
+++ b/src/cpu/Kconfig
@@ -16,6 +16,12 @@ config DCACHE_RAM_BASE
 config DCACHE_RAM_SIZE
 	hex
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+
+config DCACHE_AP_STACK_SIZE
+	hex
+
 config SMP
 	bool
 	default y if MAX_CPUS != 1
diff --git a/src/cpu/amd/car/cache_as_ram.inc b/src/cpu/amd/car/cache_as_ram.inc
index 769e5cfaa6..1c22447d2c 100644
--- a/src/cpu/amd/car/cache_as_ram.inc
+++ b/src/cpu/amd/car/cache_as_ram.inc
@@ -24,9 +24,10 @@
 
 #define CacheSize		CONFIG_DCACHE_RAM_SIZE
 #define CacheBase		(0xd0000 - CacheSize)
+#define CacheSizeBSPStack	CONFIG_DCACHE_BSP_STACK_SIZE
 
 /* For CAR with Fam10h. */
-#define CacheSizeAPStack	0x400 /* 1K */
+#define CacheSizeAPStack	CONFIG_DCACHE_AP_STACK_SIZE
 
 #define MSR_MCFG_BASE		0xC0010058
 #define MSR_FAM10		0xC001102A
diff --git a/src/cpu/amd/geode_gx2/Kconfig b/src/cpu/amd/geode_gx2/Kconfig
index e00fea4eac..b867e3701b 100644
--- a/src/cpu/amd/geode_gx2/Kconfig
+++ b/src/cpu/amd/geode_gx2/Kconfig
@@ -37,6 +37,14 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x04000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x1000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 config GEODE_VSA
 	bool
 	default y
diff --git a/src/cpu/amd/geode_lx/Kconfig b/src/cpu/amd/geode_lx/Kconfig
index 6001cc75b6..d799d6b394 100644
--- a/src/cpu/amd/geode_lx/Kconfig
+++ b/src/cpu/amd/geode_lx/Kconfig
@@ -19,6 +19,14 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x8000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x2000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 config GEODE_VSA
 	bool
 	default y
diff --git a/src/cpu/amd/model_10xxx/Kconfig b/src/cpu/amd/model_10xxx/Kconfig
index cd69caecf3..4b5cdedaa1 100644
--- a/src/cpu/amd/model_10xxx/Kconfig
+++ b/src/cpu/amd/model_10xxx/Kconfig
@@ -30,6 +30,14 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x0c000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x2000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 config UDELAY_IO
 	bool
 	default n
diff --git a/src/cpu/amd/model_10xxx/init_cpus.c b/src/cpu/amd/model_10xxx/init_cpus.c
index 62ba0b04f1..7e79307c89 100644
--- a/src/cpu/amd/model_10xxx/init_cpus.c
+++ b/src/cpu/amd/model_10xxx/init_cpus.c
@@ -250,6 +250,14 @@ static u32 init_cpus(u32 cpu_init_detectedx, struct sys_info *sysinfo)
 	u32 apicid;
 	struct node_core_id id;
 
+	uint32_t max_ap_stack_region_size = CONFIG_MAX_CPUS * CONFIG_DCACHE_AP_STACK_SIZE;
+	uint32_t bsp_stack_region_lower_boundary = CONFIG_DCACHE_RAM_BASE + (CONFIG_DCACHE_RAM_SIZE / 2);
+	void * lower_stack_region_boundary = (void*)(bsp_stack_region_lower_boundary - max_ap_stack_region_size);
+	if (((void*)(sysinfo + 1)) > lower_stack_region_boundary)
+		printk(BIOS_WARNING,
+			"sysinfo extends into stack region (sysinfo range: [%p,%p] lower stack region boundary: %p)\n",
+			sysinfo, sysinfo + 1, lower_stack_region_boundary);
+
 	/*
 	 * already set early mtrr in cache_as_ram.inc
 	 */
diff --git a/src/cpu/amd/socket_754/Kconfig b/src/cpu/amd/socket_754/Kconfig
index 3ddaea0a9a..395fc788c4 100644
--- a/src/cpu/amd/socket_754/Kconfig
+++ b/src/cpu/amd/socket_754/Kconfig
@@ -20,4 +20,12 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x08000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x2000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 endif # CPU_AMD_SOCKET_754
diff --git a/src/cpu/amd/socket_940/Kconfig b/src/cpu/amd/socket_940/Kconfig
index 1ca23e7410..a481ded55a 100644
--- a/src/cpu/amd/socket_940/Kconfig
+++ b/src/cpu/amd/socket_940/Kconfig
@@ -21,4 +21,12 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x08000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x2000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 endif # CPU_AMD_SOCKET_940
diff --git a/src/cpu/amd/socket_S1G1/Kconfig b/src/cpu/amd/socket_S1G1/Kconfig
index f88f64a9cd..2c79e1fca5 100644
--- a/src/cpu/amd/socket_S1G1/Kconfig
+++ b/src/cpu/amd/socket_S1G1/Kconfig
@@ -31,4 +31,12 @@ config DCACHE_RAM_SIZE
 	hex
 	default 0x08000
 
+config DCACHE_BSP_STACK_SIZE
+	hex
+	default 0x2000
+
+config DCACHE_AP_STACK_SIZE
+	hex
+	default 0x400
+
 endif