Matt DeVillier (matt.devillier@gmail.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/18385
-gerrit
commit c3622a5f162e37a532b02eac2aec809920627be8 Author: Matt DeVillier matt.devillier@gmail.com Date: Thu Feb 16 11:36:16 2017 -0600
lynxpoint/broadwell: fix PCH power optimizer
Setting both bits 27 and 7 of PCH register PMSYNC_CFG (PMSYNC Configuration; offset 0x33c8) causes pre-OS display init to fail on HSW-U/Lynxpoint and BDW-U ChromeOS devices when the VBIOS/GOP driver is run after the register is set. A re-examination of Intel's reference code reveals that bit 7 should be set for the LP PCH, and bit 27 for non-LP, but not both simultaneously.
The previous workaround was to disable the entire power optimizer section via a Kconfig option, which isn't ideal.
Test: unset bit 27 of PMSYNC_CFG and boot google/lulu, observe functional pre-OS video output
Change-Id: I446e169d23dd446710a1648f0a9b9599568b80aa Signed-off-by: Matt DeVillier matt.devillier@gmail.com --- src/soc/intel/broadwell/lpc.c | 2 +- src/southbridge/intel/lynxpoint/lpc.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/src/soc/intel/broadwell/lpc.c b/src/soc/intel/broadwell/lpc.c index c1600c5..610b977 100644 --- a/src/soc/intel/broadwell/lpc.c +++ b/src/soc/intel/broadwell/lpc.c @@ -262,7 +262,7 @@ static const struct reg_script pch_pm_init_script[] = { REG_MMIO_WRITE32(RCBA_BASE_ADDRESS + 0x3354, 0x00000001), /* Power Optimizer */ REG_MMIO_OR32(RCBA_BASE_ADDRESS + 0x33d4, 0x08000000), - REG_MMIO_OR32(RCBA_BASE_ADDRESS + 0x33c8, 0x08000080), + REG_MMIO_OR32(RCBA_BASE_ADDRESS + 0x33c8, 0x00000080), REG_MMIO_WRITE32(RCBA_BASE_ADDRESS + 0x2b10, 0x0000883c), REG_MMIO_WRITE32(RCBA_BASE_ADDRESS + 0x2b14, 0x1e0a4616), REG_MMIO_WRITE32(RCBA_BASE_ADDRESS + 0x2b24, 0x40000005), diff --git a/src/southbridge/intel/lynxpoint/lpc.c b/src/southbridge/intel/lynxpoint/lpc.c index 04cb0bd..d295c88 100644 --- a/src/southbridge/intel/lynxpoint/lpc.c +++ b/src/southbridge/intel/lynxpoint/lpc.c @@ -347,7 +347,7 @@ const struct rcba_config_instruction lpt_lp_pm_rcba[] = { RCBA_RMW_REG_32(0x3350, 0, 0x022ddfff), RCBA_RMW_REG_32(0x3354, 0, 0x00000001), RCBA_RMW_REG_32(0x33d4, ~0, 0x08000000), /* Power Optimizer */ - RCBA_RMW_REG_32(0x33c8, ~0, 0x08000080), /* Power Optimizer */ + RCBA_RMW_REG_32(0x33c8, ~0, 0x00000080), /* Power Optimizer */ RCBA_RMW_REG_32(0x2b10, 0, 0x0000883c), /* Power Optimizer */ RCBA_RMW_REG_32(0x2b14, 0, 0x1e0a4616), /* Power Optimizer */ RCBA_RMW_REG_32(0x2b24, 0, 0x40000005), /* Power Optimizer */