drm/nouveau/bios: update gpio parsing apis to match current design

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/include/subdev/bios/gpio.h

@@ -25,9 +25,11 @@ struct dcb_gpio_func {
 	u8 param;
 };
 
-u16 dcb_gpio_table(struct nouveau_bios *);
-u16 dcb_gpio_entry(struct nouveau_bios *, int idx, int ent, u8 *ver);
-int dcb_gpio_parse(struct nouveau_bios *, int idx, u8 func, u8 line,
+u16 dcb_gpio_table(struct nouveau_bios *, u8 *ver, u8 *hdr, u8 *cnt, u8 *len);
+u16 dcb_gpio_entry(struct nouveau_bios *, int idx, int ent, u8 *ver, u8 *len);
+u16 dcb_gpio_parse(struct nouveau_bios *, int idx, int ent, u8 *ver, u8 *len,
 		   struct dcb_gpio_func *);
+u16 dcb_gpio_match(struct nouveau_bios *, int idx, u8 func, u8 line,
+		   u8 *ver, u8 *len, struct dcb_gpio_func *);
 
 #endif

drivers/gpu/drm/nouveau/core/subdev/bios/gpio.c

@@ -27,84 +27,105 @@
 #include <subdev/bios/gpio.h>
 
 u16
-dcb_gpio_table(struct nouveau_bios *bios)
+dcb_gpio_table(struct nouveau_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
 {
-	u8  ver, hdr, cnt, len;
-	u16 dcb = dcb_table(bios, &ver, &hdr, &cnt, &len);
+	u16 data = 0x0000;
+	u16 dcb = dcb_table(bios, ver, hdr, cnt, len);
 	if (dcb) {
-		if (ver >= 0x30 && hdr >= 0x0c)
-			return nv_ro16(bios, dcb + 0x0a);
-		if (ver >= 0x22 && nv_ro08(bios, dcb - 1) >= 0x13)
-			return nv_ro16(bios, dcb - 0x0f);
+		if (*ver >= 0x30 && *hdr >= 0x0c)
+			data = nv_ro16(bios, dcb + 0x0a);
+		else
+		if (*ver >= 0x22 && nv_ro08(bios, dcb - 1) >= 0x13)
+			data = nv_ro16(bios, dcb - 0x0f);
+
+		if (data) {
+			*ver = nv_ro08(bios, data + 0x00);
+			if (*ver < 0x30) {
+				*hdr = 3;
+				*cnt = nv_ro08(bios, data + 0x02);
+				*len = nv_ro08(bios, data + 0x01);
+			} else
+			if (*ver <= 0x41) {
+				*hdr = nv_ro08(bios, data + 0x01);
+				*cnt = nv_ro08(bios, data + 0x02);
+				*len = nv_ro08(bios, data + 0x03);
+			} else {
+				data = 0x0000;
+			}
+		}
 	}
-	return 0x0000;
+	return data;
 }
 
 u16
-dcb_gpio_entry(struct nouveau_bios *bios, int idx, int ent, u8 *ver)
+dcb_gpio_entry(struct nouveau_bios *bios, int idx, int ent, u8 *ver, u8 *len)
 {
-	u16 gpio = dcb_gpio_table(bios);
-	if (gpio) {
-		*ver = nv_ro08(bios, gpio);
-		if (*ver < 0x30 && ent < nv_ro08(bios, gpio + 2))
-			return gpio + 3 + (ent * nv_ro08(bios, gpio + 1));
-		else if (ent < nv_ro08(bios, gpio + 2))
-			return gpio + nv_ro08(bios, gpio + 1) +
-			       (ent * nv_ro08(bios, gpio + 3));
-	}
+	u8  hdr, cnt;
+	u16 gpio = !idx ? dcb_gpio_table(bios, ver, &hdr, &cnt, len) : 0x0000;
+	if (gpio && ent < cnt)
+		return gpio + hdr + (ent * *len);
 	return 0x0000;
 }
 
-int
-dcb_gpio_parse(struct nouveau_bios *bios, int idx, u8 func, u8 line,
+u16
+dcb_gpio_parse(struct nouveau_bios *bios, int idx, int ent, u8 *ver, u8 *len,
 	       struct dcb_gpio_func *gpio)
 {
-	u8  ver, hdr, cnt, len;
-	u16 entry;
-	int i = -1;
-
-	while ((entry = dcb_gpio_entry(bios, idx, ++i, &ver))) {
-		if (ver < 0x40) {
-			u16 data = nv_ro16(bios, entry);
+	u16 data = dcb_gpio_entry(bios, idx, ent, ver, len);
+	if (data) {
+		if (*ver < 0x40) {
+			u16 info = nv_ro16(bios, data);
 			*gpio = (struct dcb_gpio_func) {
-				.line = (data & 0x001f) >> 0,
-				.func = (data & 0x07e0) >> 5,
-				.log[0] = (data & 0x1800) >> 11,
-				.log[1] = (data & 0x6000) >> 13,
-				.param = !!(data & 0x8000),
+				.line = (info & 0x001f) >> 0,
+				.func = (info & 0x07e0) >> 5,
+				.log[0] = (info & 0x1800) >> 11,
+				.log[1] = (info & 0x6000) >> 13,
+				.param = !!(info & 0x8000),
 			};
 		} else
-		if (ver < 0x41) {
-			u32 data = nv_ro32(bios, entry);
+		if (*ver < 0x41) {
+			u32 info = nv_ro32(bios, data);
 			*gpio = (struct dcb_gpio_func) {
-				.line = (data & 0x0000001f) >> 0,
-				.func = (data & 0x0000ff00) >> 8,
-				.log[0] = (data & 0x18000000) >> 27,
-				.log[1] = (data & 0x60000000) >> 29,
-				.param = !!(data & 0x80000000),
+				.line = (info & 0x0000001f) >> 0,
+				.func = (info & 0x0000ff00) >> 8,
+				.log[0] = (info & 0x18000000) >> 27,
+				.log[1] = (info & 0x60000000) >> 29,
+				.param = !!(info & 0x80000000),
 			};
 		} else {
-			u32 data = nv_ro32(bios, entry + 0);
-			u8 data1 = nv_ro32(bios, entry + 4);
+			u32 info = nv_ro32(bios, data + 0);
+			u8 info1 = nv_ro32(bios, data + 4);
 			*gpio = (struct dcb_gpio_func) {
-				.line = (data & 0x0000003f) >> 0,
-				.func = (data & 0x0000ff00) >> 8,
-				.log[0] = (data1 & 0x30) >> 4,
-				.log[1] = (data1 & 0xc0) >> 6,
-				.param = !!(data & 0x80000000),
+				.line = (info & 0x0000003f) >> 0,
+				.func = (info & 0x0000ff00) >> 8,
+				.log[0] = (info1 & 0x30) >> 4,
+				.log[1] = (info1 & 0xc0) >> 6,
+				.param = !!(info & 0x80000000),
 			};
 		}
+	}
+
+	return data;
+}
 
+u16
+dcb_gpio_match(struct nouveau_bios *bios, int idx, u8 func, u8 line,
+	       u8 *ver, u8 *len, struct dcb_gpio_func *gpio)
+{
+	u8  hdr, cnt, i = 0;
+	u16 data;
+
+	while ((data = dcb_gpio_parse(bios, idx, i++, ver, len, gpio))) {
 		if ((line == 0xff || line == gpio->line) &&
 		    (func == 0xff || func == gpio->func))
-			return 0;
+			return data;
 	}
 
 	/* DCB 2.2, fixed TVDAC GPIO data */
-	if ((entry = dcb_table(bios, &ver, &hdr, &cnt, &len))) {
-		if (ver >= 0x22 && ver < 0x30 && func == DCB_GPIO_TVDAC0) {
-			u8 conf = nv_ro08(bios, entry - 5);
-			u8 addr = nv_ro08(bios, entry - 4);
+	if ((data = dcb_table(bios, ver, &hdr, &cnt, len))) {
+		if (*ver >= 0x22 && *ver < 0x30 && func == DCB_GPIO_TVDAC0) {
+			u8 conf = nv_ro08(bios, data - 5);
+			u8 addr = nv_ro08(bios, data - 4);
 			if (conf & 0x01) {
 				*gpio = (struct dcb_gpio_func) {
 					.func = DCB_GPIO_TVDAC0,
@@ -112,10 +133,11 @@ dcb_gpio_parse(struct nouveau_bios *bios, int idx, u8 func, u8 line,
 					.log[0] = !!(conf & 0x02),
 					.log[1] =  !(conf & 0x02),
 				};
-				return 0;
+				*ver = 0x00;
+				return data;
 			}
 		}
 	}
 
-	return -EINVAL;
+	return 0x0000;
 }

drivers/gpu/drm/nouveau/core/subdev/gpio/base.c

@@ -43,10 +43,15 @@ static int
 nouveau_gpio_find(struct nouveau_gpio *gpio, int idx, u8 tag, u8 line,
 		  struct dcb_gpio_func *func)
 {
+	struct nouveau_bios *bios = nouveau_bios(gpio);
+	u8  ver, len;
+	u16 data;
+
 	if (line == 0xff && tag == 0xff)
 		return -EINVAL;
 
-	if (!dcb_gpio_parse(nouveau_bios(gpio), idx, tag, line, func))
+	data = dcb_gpio_match(bios, idx, tag, line, &ver, &len, func);
+	if (data)
 		return 0;
 
 	/* Apple iMac G4 NV18 */

drivers/gpu/drm/nouveau/core/subdev/gpio/nv50.c

@@ -33,11 +33,11 @@ nv50_gpio_reset(struct nouveau_gpio *gpio)
 {
 	struct nouveau_bios *bios = nouveau_bios(gpio);
 	struct nv50_gpio_priv *priv = (void *)gpio;
+	u8 ver, len;
 	u16 entry;
-	u8 ver;
 	int ent = -1;
 
-	while ((entry = dcb_gpio_entry(bios, 0, ++ent, &ver))) {
+	while ((entry = dcb_gpio_entry(bios, 0, ++ent, &ver, &len))) {
 		static const u32 regs[] = { 0xe100, 0xe28c };
 		u32 data = nv_ro32(bios, entry);
 		u8  line =   (data & 0x0000001f);

drivers/gpu/drm/nouveau/core/subdev/gpio/nvd0.c

@@ -33,11 +33,11 @@ nvd0_gpio_reset(struct nouveau_gpio *gpio)
 {
 	struct nouveau_bios *bios = nouveau_bios(gpio);
 	struct nvd0_gpio_priv *priv = (void *)gpio;
+	u8 ver, len;
 	u16 entry;
-	u8 ver;
 	int ent = -1;
 
-	while ((entry = dcb_gpio_entry(bios, 0, ++ent, &ver))) {
+	while ((entry = dcb_gpio_entry(bios, 0, ++ent, &ver, &len))) {
 		u32 data = nv_ro32(bios, entry);
 		u8  line =   (data & 0x0000003f);
 		u8  defs = !!(data & 0x00000080);