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authorNico Huber <nico.h@gmx.de>2018-05-26 20:34:21 +0200
committerNico Huber <nico.h@gmx.de>2018-05-31 15:09:30 +0000
commit6197b7698875271a2b72e730040ec7e9260a454c (patch)
treee72c8e2392d0293cd8461468855cdf111424b7f9 /src/include
parentb4953a93aa855afcf801d6f7d48df18f31ee2598 (diff)
downloadcoreboot-6197b7698875271a2b72e730040ec7e9260a454c.tar.xz
cpu/x86/mtrr: Prepare for ROM_SIZE > 16MiB
Most, if not all, chipsets have MMIO between 0xfe000000 and 0xff000000. So don't try to cache more than 16MiB of the ROM. It's also common that at most 16MiB are memory mapped. Change-Id: I5dfa2744190a34c56c86e108a8c50dca9d428268 Signed-off-by: Nico Huber <nico.h@gmx.de> Reviewed-on: https://review.coreboot.org/26567 Reviewed-by: Aaron Durbin <adurbin@chromium.org> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/include')
-rw-r--r--src/include/cpu/x86/mtrr.h18
1 files changed, 14 insertions, 4 deletions
diff --git a/src/include/cpu/x86/mtrr.h b/src/include/cpu/x86/mtrr.h
index f1e067a26b..dde9a2888b 100644
--- a/src/include/cpu/x86/mtrr.h
+++ b/src/include/cpu/x86/mtrr.h
@@ -1,6 +1,8 @@
#ifndef CPU_X86_MTRR_H
#define CPU_X86_MTRR_H
+#include <commonlib/helpers.h>
+
/* These are the region types */
#define MTRR_TYPE_UNCACHEABLE 0
#define MTRR_TYPE_WRCOMB 1
@@ -152,12 +154,20 @@ static inline unsigned int fls(unsigned int x)
to get a power of 2 again, for a single MTRR. */
#define CAR_END (CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE)
#if CAR_END > OPTIMAL_CACHE_ROM_BASE
-# define CACHE_ROM_SIZE _ALIGN_DOWN_POW2(_FROM_4G_TOP(CAR_END))
+# define CAR_CACHE_ROM_SIZE _ALIGN_DOWN_POW2(_FROM_4G_TOP(CAR_END))
#else
-# define CACHE_ROM_SIZE OPTIMAL_CACHE_ROM_SIZE
+# define CAR_CACHE_ROM_SIZE OPTIMAL_CACHE_ROM_SIZE
+#endif
+#if ((CAR_CACHE_ROM_SIZE & (CAR_CACHE_ROM_SIZE - 1)) != 0)
+# error "CAR CACHE_ROM_SIZE is not a power of 2, _POW2_MASK needs refinement."
#endif
-#if ((CACHE_ROM_SIZE & (CACHE_ROM_SIZE - 1)) != 0)
-# error "CACHE_ROM_SIZE is not a power of 2, _POW2_MASK needs refinement."
+
+/* Last but not least, most (if not all) chipsets have MMIO
+ between 0xfe000000 and 0xff000000, so limit to 16MiB. */
+#if CAR_CACHE_ROM_SIZE >= 16 * MiB
+# define CACHE_ROM_SIZE (16 * MiB)
+#else
+# define CACHE_ROM_SIZE CAR_CACHE_ROM_SIZE
#endif
#define CACHE_ROM_BASE _FROM_4G_TOP(CACHE_ROM_SIZE)