nb/intel/sandybridge: Add support for DPR
Include DPR in the memory map calculations if enabled. DPR is required
for Intel TXT support.
TEST=Boot Debian 10 and see the DPR memory being reserved in E820 and
cbmem logs:
"BIOS-e820: [mem 0x000000007fc09000-0x00000000829fffff] reserved"
"TSEG base 0x80000000 size 8M"
"DPR base 0x7fd00000 size 3M"
Signed-off-by: Michał Żygowski <michal.zygowski@3mdeb.com>
Change-Id: Ia22e49ba58709acfa0afe0921aa71d83cc06c129
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59512
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/northbridge/intel/sandybridge/northbridge.c b/src/northbridge/intel/sandybridge/northbridge.c
index bd4d107..f04c4f5 100644
--- a/src/northbridge/intel/sandybridge/northbridge.c
+++ b/src/northbridge/intel/sandybridge/northbridge.c
@@ -14,6 +14,7 @@
#include "chip.h"
#include "sandybridge.h"
#include <cpu/intel/smm_reloc.h>
+#include <security/intel/txt/txt_platform.h>
/* IGD UMA memory */
static uint64_t uma_memory_base = 0;
@@ -85,9 +86,11 @@
{
uint64_t tom, me_base, touud;
uint32_t tseg_base, uma_size, tolud;
+ uint32_t dpr_base_k, dpr_size_k;
uint16_t ggc;
unsigned long long tomk;
unsigned long index = 3;
+ const union dpr_register dpr = txt_get_chipset_dpr();
pci_dev_read_resources(dev);
@@ -184,6 +187,15 @@
uma_memory_size += uma_size * 1024ULL;
printk(BIOS_DEBUG, "TSEG base 0x%08x size %uM\n", tseg_base, uma_size >> 10);
+ /* Calculate DMA Protected Region if enabled */
+ if (dpr.epm && dpr.size) {
+ dpr_size_k = dpr.size * MiB / KiB;
+ tomk -= dpr_size_k;
+ dpr_base_k = (tseg_base - dpr.size * MiB) / KiB;
+ reserved_ram_resource(dev, index++, dpr_base_k, dpr_size_k);
+ printk(BIOS_DEBUG, "DPR base 0x%08x size %uM\n", dpr_base_k * KiB, dpr.size);
+ }
+
printk(BIOS_INFO, "Available memory below 4GB: %lluM\n", tomk >> 10);
/* Report the memory regions */