Change in flashrom[staging]: ichspi: "Fix" access permission reporting for regions > 7

[Nico Huber (Code Review)]

Nico Huber has uploaded this change for review. ( https://review.coreboot.org/21106

Change subject: ichspi: "Fix" access permission reporting for regions > 7
......................................................................

ichspi: "Fix" access permission reporting for regions > 7

Can't find bits that tell us the actual permissions in charge. So report
them as unknown.

Change-Id: Ib73f95e0348f5c6d89988e3ea3529af0ec3b23a6
Signed-off-by: Nico Huber 
---
M ichspi.c
1 file changed, 18 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/06/21106/1

diff --git a/ichspi.c b/ichspi.c
index 5f3e394..9ee8044 100644
--- a/ichspi.c
+++ b/ichspi.c
@@ -1543,6 +1543,7 @@
    static const char *const access_names[4] = {
    	"locked", "read-only", "write-only", "read-write"
    };
+	const int rwperms_unknown = ARRAY_SIZE(access_names);
    static const char *const region_names[5] = {
    	"Flash Descriptor", "BIOS", "Management Engine",
    	"Gigabit Ethernet", "Platform Data"
@@ -1550,10 +1551,20 @@
    const char *const region_name = i < ARRAY_SIZE(region_names) ? region_names[i] : "unknown";

uint32_t base, limit;
-	int rwperms = (((ICH_BRWA(frap) >> i) & 1) << 1) |
-		      (((ICH_BRRA(frap) >> i) & 1) << 0);
+	int rwperms;
    int offset = ICH9_REG_FREG0 + i * 4;
    uint32_t freg = mmio_readl(ich_spibar + offset);
+
+	if (i < 8) {
+		rwperms = (((ICH_BRWA(frap) >> i) & 1) << 1) |
+			  (((ICH_BRRA(frap) >> i) & 1) << 0);
+	} else {
+		/* Datasheets don't define any access bits for regions > 7. We
+		   can't rely on the actual descriptor settings either as there
+		   are several overrides for them (those by other masters are
+		   not even readable by us, *shrug*). */
+		rwperms = rwperms_unknown;
+	}

base  = ICH_FREG_BASE(freg);
    limit = ICH_FREG_LIMIT(freg);
@@ -1569,6 +1580,11 @@
    		 region_name, base, limit, access_names[rwperms]);
    	return 0;
    }
+	if (rwperms == rwperms_unknown) {
+		msg_pdbg("FREG%i: %s region (0x%08x-0x%08x) has unknown permissions.\n",
+			 i, region_name, base, limit);
+		return 0;
+	}

msg_pwarn("FREG%i: Warning: %s region (0x%08x-0x%08x) is %s.\n", i,
    	  region_name, base, limit, access_names[rwperms]);