From 148a4f5681263a24408d5988261bb3fd6b3c647e Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Sun, 10 Apr 2011 07:41:56 +0000 Subject: [PATCH] i945: improve get_top_of_ram() The current version doesn't honor TSEG, and fails to report the correct top of RAM if IGD is disabled. This is because it uses the BSM (base of stolen RAM) register. In that case, we should use the TOLUD register. Signed-off-by: Sven Schnelle Acked-by: Stefan Reinauer git-svn-id: svn://svn.coreboot.org/coreboot/trunk@6483 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1 --- src/northbridge/intel/i945/raminit.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/src/northbridge/intel/i945/raminit.c b/src/northbridge/intel/i945/raminit.c index 8b7ffa148..a9e4a910e 100644 --- a/src/northbridge/intel/i945/raminit.c +++ b/src/northbridge/intel/i945/raminit.c @@ -3192,9 +3192,33 @@ void sdram_initialize(int boot_path, const u8 *spd_addresses) unsigned long get_top_of_ram(void) { - /* This will not work if TSEG is in place! */ - u32 tom = pci_read_config32(PCI_DEV(0,2,0), 0x5c); + u32 tom; + if (pci_read_config8(PCI_DEV(0, 0x0, 0), DEVEN) & ((1 << 4) | (1 << 3))) { + /* IGD enabled, get top of Memory from BSM register */ + tom = pci_read_config32(PCI_DEV(0,2,0), 0x5c); + } else { + tom = (pci_read_config8(PCI_DEV(0,0,0), TOLUD) & 0xf7) << 24; + } + + /* if TSEG enabled subtract size */ + switch(pci_read_config8(PCI_DEV(0, 0, 0), ESMRAM)) { + case 0x01: + /* 1MB TSEG */ + tom -= 0x10000; + break; + case 0x03: + /* 2MB TSEG */ + tom -= 0x20000; + break; + case 0x05: + /* 8MB TSEG */ + tom -= 0x80000; + break; + default: + /* TSEG either disabled or invalid */ + break; + } return (unsigned long) tom; } -- 2.25.1