From 77516ca79225f91fdcb4fc837f141a320de5371a Mon Sep 17 00:00:00 2001 From: Angel Pons Date: Thu, 10 Dec 2020 16:43:25 +0100 Subject: [PATCH] nb/intel/sandybridge: Correct late DMI init sequence Based on reference code, update the DMI ASPM setup steps. Change-Id: I1248305b2f76f48f4e6910de1a6980e942f16945 Signed-off-by: Angel Pons Reviewed-on: https://review.coreboot.org/c/coreboot/+/48536 Reviewed-by: Patrick Rudolph Tested-by: build bot (Jenkins) --- .../intel/sandybridge/northbridge.c | 34 +++++++++++++------ 1 file changed, 23 insertions(+), 11 deletions(-) diff --git a/src/northbridge/intel/sandybridge/northbridge.c b/src/northbridge/intel/sandybridge/northbridge.c index 4d87878fa2..dc1be32ee1 100644 --- a/src/northbridge/intel/sandybridge/northbridge.c +++ b/src/northbridge/intel/sandybridge/northbridge.c @@ -256,17 +256,15 @@ static void northbridge_dmi_init(struct device *dev) { const bool is_sandy = is_sandybridge(); - u32 reg32; + const u8 stepping = cpu_stepping(); - /* Clear error status bits */ - DMIBAR32(DMIUESTS) = 0xffffffff; - DMIBAR32(DMICESTS) = 0xffffffff; + u32 reg32; /* Steps prior to DMI ASPM */ if (is_sandy) { reg32 = DMIBAR32(0x250); - reg32 &= ~((1 << 22) | (1 << 20)); - reg32 |= (1 << 21); + reg32 &= ~(7 << 20); + reg32 |= (2 << 20); DMIBAR32(0x250) = reg32; } @@ -274,12 +272,14 @@ static void northbridge_dmi_init(struct device *dev) reg32 |= (1 << 29); DMIBAR32(DMILLTC) = reg32; - if (!is_sandy || cpu_stepping() >= SNB_STEP_D0) { - reg32 = DMIBAR32(0x1f8); - reg32 |= (1 << 16); - DMIBAR32(0x1f8) = reg32; + if (is_sandy && stepping == SNB_STEP_C0) { + reg32 = DMIBAR32(0xbc8); + reg32 &= ~(0xfff << 7); + reg32 |= (0x7d3 << 7); + DMIBAR32(0xbc8) = reg32; + } - } else if (!is_sandy || cpu_stepping() >= SNB_STEP_D1) { + if (!is_sandy || stepping >= SNB_STEP_D1) { reg32 = DMIBAR32(0x1f8); reg32 &= ~(1 << 26); reg32 |= (1 << 16); @@ -288,8 +288,20 @@ static void northbridge_dmi_init(struct device *dev) reg32 = DMIBAR32(0x1fc); reg32 |= (1 << 12) | (1 << 23); DMIBAR32(0x1fc) = reg32; + + } else if (stepping >= SNB_STEP_D0) { + reg32 = DMIBAR32(0x1f8); + reg32 |= (1 << 16); + DMIBAR32(0x1f8) = reg32; } + /* Clear error status bits */ + DMIBAR32(DMIUESTS) = 0xffffffff; + DMIBAR32(DMICESTS) = 0xffffffff; + + if (!is_sandy) + DMIBAR32(0xc34) = 0xffffffff; + /* Enable ASPM on SNB link, should happen before PCH link */ if (is_sandy) { reg32 = DMIBAR32(0xd04);