soc/intel/common/fast_spi: Add extended decode window support

This change enables support for configuration of extended BIOS
region decode window. This configuration needs to be performed
as early as possible in the boot flow. This is required to
ensure that any access to the SPI flash region below 16MiB in
coreboot is decoded correctly. The configuration for the extended
BIOS window if required is done as part of fast_spi_early_init().

Changes include:
1. Make a call to fast_spi_enable_ext_bios() before the bus master
and memory space is enabled for the fast SPI controller.
2. Added a helper function fast_spi_enable_ext_bios() which calls
fast_spi_get_ext_bios_window() to get details about the extended
BIOS window from the boot media map.
3. Depending upon the SPI flash device used by the mainboard and
the size of the BIOS region in the flashmap, this function will
have to perform this additional configuration only if the BIOS
region is greater than 16MiB
4. Adddditionally, set up the general purpose memory range
registers in DMI.

BUG=b:171534504

Signed-off-by: Srinidhi N Kaushik <srinidhi.n.kaushik@intel.com>
Signed-off-by: Furquan Shaikh <furquan@google.com>
Change-Id: Idafd8be0261892122d0b5a95d9ce9d5604a10cf2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47990
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/src/soc/intel/common/block/include/intelblocks/fast_spi.h b/src/soc/intel/common/block/include/intelblocks/fast_spi.h
index 0a7e64dad4..81437b6e6a 100644
--- a/src/soc/intel/common/block/include/intelblocks/fast_spi.h
+++ b/src/soc/intel/common/block/include/intelblocks/fast_spi.h
@@ -73,12 +73,15 @@ bool fast_spi_wpd_status(void);
  * Enable SPI Write protect.
  */
 void fast_spi_enable_wp(void);
-
 /*
  * Get base and size of extended BIOS decode window used at runtime in host address space. If
  * the BIOS region is not greater than 16MiB, then this function returns 0 for both base and
  * size.
  */
 void fast_spi_get_ext_bios_window(uintptr_t *base, size_t *size);
+/*
+ * SOC function to get SPI-DMI Destination Id
+ */
+uint32_t soc_get_spi_dmi_destination_id(void);
 
 #endif	/* SOC_INTEL_COMMON_BLOCK_FAST_SPI_H */