ifdtool: Enable GbE/PDR/EC region access only if they exist

Instead of assuming GbE/PDR/EC regions may exist or not, check if there
is a valid region defined in the descriptor and set the region access
permissions based on that.

The net effect change is to enable the use of the PDR region on the
sarien platform, which also uses the GbE and EC regions.

This results in the following example changes:

mb/google/sarien (GbE, PDR, EC)
.      DESC BIOS ME GbE PDR EC
-BIOS  r    rw      rw      r
-------------------------------
+BIOS  r    rw      rw  rw  r

mb/google/eve: (no GbE, no PDR, no EC)
.      DESC BIOS ME GbE PDR EC
-BIOS  r    rw      rw      r
-ME    r         rw r
-GbE   r            rw
-EC    r                    rw
-------------------------------
+BIOS  r    rw
+ME    r         rw
+GbE
+EC

BUG=b:134703987

Change-Id: I7aeffc8f8194638c6012340b43aea8f8460d268a
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33273
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

2 files changed, 78 insertions, 30 deletions

diff --git a/util/ifdtool/ifdtool.c b/util/ifdtool/ifdtool.c
index 6c5e784569..a1a327f6ed 100644
--- a/util/ifdtool/ifdtool.c
+++ b/util/ifdtool/ifdtool.c
@@ -925,15 +925,24 @@ static void set_chipdensity(const char *filename, char *image, int size,
 	write_image(filename, image, size);
 }
 
+static int check_region(const frba_t *frba, unsigned int region_type)
+{
+	region_t region;
+
+	if (!frba)
+		return 0;
+
+	region = get_region(frba, region_type);
+	return !!((region.base < region.limit) && (region.size > 0));
+}
+
 static void lock_descriptor(const char *filename, char *image, int size)
 {
 	int wr_shift, rd_shift;
 	fmba_t *fmba = find_fmba(image, size);
+	const frba_t *frba = find_frba(image, size);
 	if (!fmba)
 		exit(EXIT_FAILURE);
-	/* TODO: Dynamically take Platform Data Region and GbE Region
-	 * into regard.
-	 */
 
 	if (ifd_version >= IFD_VERSION_2) {
 		wr_shift = FLMSTR_WR_SHIFT_V2;
@@ -969,36 +978,66 @@ static void lock_descriptor(const char *filename, char *image, int size)
 	case PLATFORM_CNL:
 	case PLATFORM_ICL:
 	case PLATFORM_SKLKBL:
-		/* CPU/BIOS can read descriptor, BIOS, EC and GbE. */
-		fmba->flmstr1 |= 0x10b << rd_shift;
-		/* CPU/BIOS can write BIOS and Gbe. */
-		fmba->flmstr1 |= 0xa << wr_shift;
-		/* ME can read descriptor, ME and GbE. */
-		fmba->flmstr2 |= 0xd << rd_shift;
+		/* CPU/BIOS can read descriptor and BIOS. */
+		fmba->flmstr1 |= (1 << REGION_DESC) << rd_shift;
+		fmba->flmstr1 |= (1 << REGION_BIOS) << rd_shift;
+		/* CPU/BIOS can write BIOS. */
+		fmba->flmstr1 |= (1 << REGION_BIOS) << wr_shift;
+		/* ME can read descriptor and ME. */
+		fmba->flmstr2 |= (1 << REGION_DESC) << rd_shift;
+		fmba->flmstr2 |= (1 << REGION_ME) << rd_shift;
 		/* ME can write ME. */
-		fmba->flmstr2 |= 0x4 << wr_shift;
-		/* GbE can read GbE and descriptor. */
-		fmba->flmstr3 |= 0x9 << rd_shift;
-		/* GbE can write GbE. */
-		fmba->flmstr3 |= 0x8 << wr_shift;
-		/* EC can read EC and descriptor. */
-		fmba->flmstr5 |= 0x101 << rd_shift;
-		/* EC can write EC region. */
-		fmba->flmstr5 |= 0x100 << wr_shift;
+		fmba->flmstr2 |= (1 << REGION_ME) << wr_shift;
+		if (check_region(frba, REGION_GBE)) {
+			/* BIOS can read/write GbE. */
+			fmba->flmstr1 |= (1 << REGION_GBE) << rd_shift;
+			fmba->flmstr1 |= (1 << REGION_GBE) << wr_shift;
+			/* ME can read GbE. */
+			fmba->flmstr2 |= (1 << REGION_GBE) << rd_shift;
+			/* GbE can read descriptor and read/write GbE.. */
+			fmba->flmstr3 |= (1 << REGION_DESC) << rd_shift;
+			fmba->flmstr3 |= (1 << REGION_GBE) << rd_shift;
+			fmba->flmstr3 |= (1 << REGION_GBE) << wr_shift;
+		}
+		if (check_region(frba, REGION_PDR)) {
+			/* BIOS can read/write PDR. */
+			fmba->flmstr1 |= (1 << REGION_PDR) << rd_shift;
+			fmba->flmstr1 |= (1 << REGION_PDR) << wr_shift;
+		}
+		if (check_region(frba, REGION_EC)) {
+			/* BIOS can read EC. */
+			fmba->flmstr1 |= (1 << REGION_EC) << rd_shift;
+			/* EC can read descriptor and read/write EC. */
+			fmba->flmstr5 |= (1 << REGION_DESC) << rd_shift;
+			fmba->flmstr5 |= (1 << REGION_EC) << rd_shift;
+			fmba->flmstr5 |= (1 << REGION_EC) << wr_shift;
+		}
 		break;
 	default:
-		/* CPU/BIOS can read descriptor, BIOS, and GbE. */
-		fmba->flmstr1 |= 0xb << rd_shift;
-		/* CPU/BIOS can write BIOS and GbE. */
-		fmba->flmstr1 |= 0xa << wr_shift;
-		/* ME can read descriptor, ME, and GbE. */
-		fmba->flmstr2 |= 0xd << rd_shift;
-		/* ME can write ME and GbE. */
-		fmba->flmstr2 |= 0xc << wr_shift;
-		/* GbE can write only GbE. */
-		fmba->flmstr3 |= 0x8 << rd_shift;
-		/* GbE can read only GbE. */
-		fmba->flmstr3 |= 0x8 << wr_shift;
+		/* CPU/BIOS can read descriptor and BIOS. */
+		fmba->flmstr1 |= (1 << REGION_DESC) << rd_shift;
+		fmba->flmstr1 |= (1 << REGION_BIOS) << rd_shift;
+		/* CPU/BIOS can write BIOS. */
+		fmba->flmstr1 |= (1 << REGION_BIOS) << wr_shift;
+		/* ME can read descriptor and ME. */
+		fmba->flmstr2 |= (1 << REGION_DESC) << rd_shift;
+		fmba->flmstr2 |= (1 << REGION_ME) << rd_shift;
+		/* ME can write ME. */
+		fmba->flmstr2 |= (1 << REGION_ME) << wr_shift;
+		if (check_region(frba, REGION_GBE)) {
+			/* BIOS can read GbE. */
+			fmba->flmstr1 |= (1 << REGION_GBE) << rd_shift;
+			/* BIOS can write GbE. */
+			fmba->flmstr1 |= (1 << REGION_GBE) << wr_shift;
+			/* ME can read GbE. */
+			fmba->flmstr2 |= (1 << REGION_GBE) << rd_shift;
+			/* ME can write GbE. */
+			fmba->flmstr2 |= (1 << REGION_GBE) << wr_shift;
+			/* GbE can write GbE. */
+			fmba->flmstr3 |= (1 << REGION_GBE) << rd_shift;
+			/* GbE can read GbE. */
+			fmba->flmstr3 |= (1 << REGION_GBE) << wr_shift;
+		}
 		break;
 	}
 
diff --git a/util/ifdtool/ifdtool.h b/util/ifdtool/ifdtool.h
index 49463b91bf..f3b9a53e06 100644
--- a/util/ifdtool/ifdtool.h
+++ b/util/ifdtool/ifdtool.h
@@ -94,6 +94,15 @@ typedef struct {
 #define MAX_REGIONS 9
 #define MAX_REGIONS_OLD 5
 
+enum flash_regions {
+	REGION_DESC,
+	REGION_BIOS,
+	REGION_ME,
+	REGION_GBE,
+	REGION_PDR,
+	REGION_EC = 8,
+};
+
 typedef struct {
 	uint32_t flreg[MAX_REGIONS];
 } __attribute__((packed)) frba_t;