drm/nouveau/bios: fix DCB v1.5 parsing

memcmp->nv_strncmp conversion, in addition to name change, should have
inverted the return value.

But nv_strncmp does not act like strncmp - it does not check for string
terminator, returns true/false instead of -1/0/1 and has different
parameters order.

Let's rename it to nv_memcmp and let it act like memcmp.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/core/include/core/object.h b/drivers/gpu/drm/nouveau/core/include/core/object.h
index 818feab..486f1a9 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/include/core/object.h
+++ b/drivers/gpu/drm/nouveau/core/include/core/object.h
@@ -175,14 +175,18 @@ nv_mo32(void *obj, u32 addr, u32 mask, u32 data)
        return temp;
 }
 
-static inline bool
-nv_strncmp(void *obj, u32 addr, u32 len, const char *str)
+static inline int
+nv_memcmp(void *obj, u32 addr, const char *str, u32 len)
 {
+       unsigned char c1, c2;
+
        while (len--) {
-               if (nv_ro08(obj, addr++) != *(str++))
-                       return false;
+               c1 = nv_ro08(obj, addr++);
+               c2 = *(str++);
+               if (c1 != c2)
+                       return c1 - c2;
        }
-       return true;
+       return 0;
 }
 
 #endif

diff --git a/drivers/gpu/drm/nouveau/core/subdev/bios/dcb.c b/drivers/gpu/drm/nouveau/core/subdev/bios/dcb.c
index 7d75038..c511971 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/subdev/bios/dcb.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/bios/dcb.c
@@ -64,7 +64,7 @@ dcb_table(struct nouveau_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
                }
        } else
        if (*ver >= 0x15) {
-               if (!nv_strncmp(bios, dcb - 7, 7, "DEV_REC")) {
+               if (!nv_memcmp(bios, dcb - 7, "DEV_REC", 7)) {
                        u16 i2c = nv_ro16(bios, dcb + 2);
                        *hdr = 4;
                        *cnt = (i2c - dcb) / 10;