diff options
| author | Bernardo Perez Priego <bernardo.perez.priego@intel.com> | 2020-01-14 15:59:19 -0800 |
|---|---|---|
| committer | Patrick Georgi <pgeorgi@google.com> | 2020-01-18 11:19:49 +0000 |
| commit | 1d8568c91413c76ee147bf6c09ae87197f7e75d7 (patch) | |
| tree | 1e879dc796826b428e8576ac5074e9b3d835e265 /src | |
| parent | 954a5b50ad9d6ee31f0f0d7abe6badf412cbe9cc (diff) | |
ec/google/wilco: Set minimum UCSI_ACPI region length
IMD provides support for small and large allocations. Region IMD Small memory is 1 KB
with 32 Bytes alignment, this region holds smaller entries without having to reserve a
whole 4 KB page. Remaining space is assigned to IMD Large to hold various regions with
4 KB alignment.
The UCSI kernel (kernel version 4.19) driver maps the UCSI_ACPI memory as not cached.
Cache mapping is set on page boundaries and all IMD Small is within the same page.
If another driver maps the memory as write-back before the UCSI driver is loaded then
the UCSI driver will fail to map the memory as not cached.
Placing UCSI_ACPI in IMD Large region will prevent this mapping issue since it will
now be located within its own page. This patch will force UCSI_ACPI region to be
located in IMD Large region.
BUG=b:144826008
Signed-off-by: Bernardo Perez Priego <bernardo.perez.priego@intel.com>
Change-Id: Id00e76dca240279773a95c8054831e05df390664
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38414
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Mathew King <mathewk@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/ec/google/wilco/chip.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/src/ec/google/wilco/chip.c b/src/ec/google/wilco/chip.c index 70e612442c..b44cbd6c64 100644 --- a/src/ec/google/wilco/chip.c +++ b/src/ec/google/wilco/chip.c @@ -28,6 +28,11 @@ #include "chip.h" /* + * Setting minimum length of UCSI_ACPI will ensure this region is placed out of IMD Small. + * Having this region out of IMD Small will prevent any memory mapping conflicts. + */ +#define UCSI_MIN_ALLOC_REGION_LEN CBMEM_SM_ROOT_SIZE +/* * The UCSI fields are defined in the UCSI specification at * https://www.intel.com/content/www/us/en/io/universal-serial-bus/usb-type-c-ucsi-spec.html * https://www.intel.com/content/www/us/en/io/universal-serial-bus/bios-implementation-of-ucsi.html @@ -175,19 +180,22 @@ static void wilco_ec_fill_ssdt_generator(struct device *dev) { struct opregion opreg; void *region_ptr; + size_t ucsi_alloc_region_len; if (!dev->enabled) return; - region_ptr = cbmem_add(CBMEM_ID_ACPI_UCSI, ucsi_region_len); + ucsi_alloc_region_len = ucsi_region_len < UCSI_MIN_ALLOC_REGION_LEN ? + UCSI_MIN_ALLOC_REGION_LEN : ucsi_region_len; + region_ptr = cbmem_add(CBMEM_ID_ACPI_UCSI, ucsi_alloc_region_len); if (!region_ptr) return; - memset(region_ptr, 0, ucsi_region_len); + memset(region_ptr, 0, ucsi_alloc_region_len); opreg.name = "UCSM"; opreg.regionspace = SYSTEMMEMORY; opreg.regionoffset = (uintptr_t)region_ptr; - opreg.regionlen = ucsi_region_len; + opreg.regionlen = ucsi_alloc_region_len; acpigen_write_scope(acpi_device_path_join(dev, "UCSI")); acpigen_write_name("_CRS"); |