diff options
author | Subrata Banik <subratabanik@google.com> | 2024-08-25 01:35:20 +0530 |
---|---|---|
committer | Subrata Banik <subratabanik@google.com> | 2024-08-28 04:11:21 +0000 |
commit | 19a22e3373092dbe64774c350ee8143030f1e19f (patch) | |
tree | bbfbcc34726d1c5edec3648392c91724b841810d /src/soc/intel/alderlake/bootblock | |
parent | 74be95213d9a12794f6a0d76443722c7fb3b84b1 (diff) |
soc/intel/adl: Prevent unconditional legacy COM ports initialization
This patch eliminates the LPC_IOE_COMA_EN and LPC_IOE_COMB_EN IO enables
from the io_enables variable in the pch_early_iorange_init() function
because lpc_io_setup_comm_a_b() is intended to activate legacy COM
ports like COM-A (0x3F8 - 0x3FF) and COM_B (0x2F8 - 0x2FF).
These COM ports are being activated unconditionally, which is
undesirable for the Intel Alder Lake platform and causes traffic over
the IO bus.
As a result, this code is being removed and platforms that select
DRIVERS_UART_8250IO can activate legacy COM ports.
BUG=b:354066052
TEST=Able to boot google/redrix to the operating system and confirm
that there was no traffic over legacy COMs while being monitored
using the eSPI analyzer.
Change-Id: I7a6e38bd151f823d37c07ee89a800489122cc209
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84080
Reviewed-by: Eric Lai <ericllai@google.com>
Reviewed-by: Dinesh Gehlot <digehlot@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/soc/intel/alderlake/bootblock')
-rw-r--r-- | src/soc/intel/alderlake/bootblock/pch.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/src/soc/intel/alderlake/bootblock/pch.c b/src/soc/intel/alderlake/bootblock/pch.c index 9041052bbb..01153489c7 100644 --- a/src/soc/intel/alderlake/bootblock/pch.c +++ b/src/soc/intel/alderlake/bootblock/pch.c @@ -98,8 +98,7 @@ static void soc_config_acpibase(void) void pch_early_iorange_init(void) { - uint16_t io_enables = LPC_IOE_COMA_EN | LPC_IOE_COMB_EN | - LPC_IOE_LPT_EN | LPC_IOE_FDD_EN | + uint16_t io_enables = LPC_IOE_LPT_EN | LPC_IOE_FDD_EN | LPC_IOE_LGE_200 | LPC_IOE_HGE_208 | LPC_IOE_KBC_60_64 | LPC_IOE_EC_62_66 | LPC_IOE_SUPERIO_2E_2F | LPC_IOE_EC_4E_4F; |