[SeaBIOS] [PATCH 3/8] SeaVGABIOS/vbe: Query driver for scanline pitch

[Patrick Rudolph]

Query the driver for the real scanline pitch in bytes.

As cbvga doesn't change the pitch on mode change, always
return the same pitch, that might exceed width times Bytes-per-pixel.

Signed-off-by: Patrick Rudolph <siro at das-labor.org>

diff --git a/vgasrc/bochsvga.c b/vgasrc/bochsvga.c
index ec5d101..458b3a8 100644
--- a/vgasrc/bochsvga.c
+++ b/vgasrc/bochsvga.c
@@ -310,6 +310,11 @@ bochsvga_save_restore(int cmd, u16 seg, void *data)
     return ret + (VBE_DISPI_INDEX_Y_OFFSET-VBE_DISPI_INDEX_XRES+1)*sizeof(u16);
 }
 
+int
+bochsvga_get_linesize(struct vgamode_s *vmode_g)
+{
+    return DIV_ROUND_UP(vmode_g->width * vga_bpp(vmode_g), 8);
+}
 
 /****************************************************************
  * Mode setting
diff --git a/vgasrc/bochsvga.h b/vgasrc/bochsvga.h
index ae5f75d..40ce6f1 100644
--- a/vgasrc/bochsvga.h
+++ b/vgasrc/bochsvga.h
@@ -52,6 +52,7 @@ int bochsvga_get_dacformat(struct vgamode_s *vmode_g);
 int bochsvga_set_dacformat(struct vgamode_s *vmode_g, int val);
 int bochsvga_save_restore(int cmd, u16 seg, void *data);
 int bochsvga_set_mode(struct vgamode_s *vmode_g, int flags);
+int bochsvga_get_linesize(struct vgamode_s *vmode_g);
 int bochsvga_setup(void);
 
 #endif // bochsvga.h
diff --git a/vgasrc/cbvga.c b/vgasrc/cbvga.c
index 49af7f9..6b3233e 100644
--- a/vgasrc/cbvga.c
+++ b/vgasrc/cbvga.c
@@ -124,6 +124,13 @@ cbvga_set_mode(struct vgamode_s *vmode_g, int flags)
     return 0;
 }
 
+int
+cbvga_get_linesize(struct vgamode_s *vmode_g)
+{
+    /* Can't change mode, always report active pitch. */
+    return GET_GLOBAL(CBlinelength);
+}
+
 #define CB_TAG_FRAMEBUFFER      0x0012
 struct cb_framebuffer {
     u32 tag;
diff --git a/vgasrc/clext.c b/vgasrc/clext.c
index da8b790..08bc9b5 100644
--- a/vgasrc/clext.c
+++ b/vgasrc/clext.c
@@ -376,6 +376,11 @@ clext_save_restore(int cmd, u16 seg, void *data)
     return stdvga_save_restore(cmd, seg, data);
 }
 
+int
+clext_get_linesize(struct vgamode_s *vmode_g)
+{
+    return DIV_ROUND_UP(vmode_g->width * vga_bpp(vmode_g), 8);
+}
 
 /****************************************************************
  * Mode setting
diff --git a/vgasrc/stdvga.c b/vgasrc/stdvga.c
index 886deca..0e24297 100644
--- a/vgasrc/stdvga.c
+++ b/vgasrc/stdvga.c
@@ -321,6 +321,11 @@ stdvga_set_dacformat(struct vgamode_s *vmode_g, int val)
     return -1;
 }
 
+int
+stdvga_get_linesize(struct vgamode_s *vmode_g)
+{
+    return DIV_ROUND_UP(vmode_g->width * vga_bpp(vmode_g), 8);
+}
 
 /****************************************************************
  * Save/Restore state
diff --git a/vgasrc/vbe.c b/vgasrc/vbe.c
index facad19..724c1ba 100644
--- a/vgasrc/vbe.c
+++ b/vgasrc/vbe.c
@@ -107,7 +107,7 @@ vbe_104f01(struct bregs *regs)
     // Basic information about mode.
     int width = GET_GLOBAL(vmode_g->width);
     int height = GET_GLOBAL(vmode_g->height);
-    int linesize = DIV_ROUND_UP(width * vga_bpp(vmode_g), 8);
+    int linesize = vgahw_get_linesize(vmode_g);
     SET_FARVAR(seg, info->bytes_per_scanline, linesize);
     SET_FARVAR(seg, info->xres, width);
     SET_FARVAR(seg, info->yres, height);
diff --git a/vgasrc/vgahw.h b/vgasrc/vgahw.h
index dab2b4d..5839643 100644
--- a/vgasrc/vgahw.h
+++ b/vgasrc/vgahw.h
@@ -139,4 +139,14 @@ static inline int vgahw_save_restore(int cmd, u16 seg, void *data) {
     return stdvga_save_restore(cmd, seg, data);
 }
 
+static inline int vgahw_get_linesize(struct vgamode_s *vmode_g) {
+    if (CONFIG_VGA_CIRRUS)
+        return clext_get_linesize(vmode_g);
+    if (CONFIG_VGA_BOCHS)
+        return bochsvga_get_linesize(vmode_g);
+    if (CONFIG_VGA_COREBOOT)
+        return cbvga_get_linesize(vmode_g);
+    return stdvga_get_linesize(vmode_g);
+}
+
 #endif // vgahw.h
diff --git a/vgasrc/vgautil.h b/vgasrc/vgautil.h
index 08c4e8d..4b6f5b9 100644
--- a/vgasrc/vgautil.h
+++ b/vgasrc/vgautil.h
@@ -17,6 +17,7 @@ int cbvga_get_dacformat(struct vgamode_s *vmode_g);
 int cbvga_set_dacformat(struct vgamode_s *vmode_g, int val);
 int cbvga_save_restore(int cmd, u16 seg, void *data);
 int cbvga_set_mode(struct vgamode_s *vmode_g, int flags);
+int cbvga_get_linesize(struct vgamode_s *vmode_g);
 int cbvga_setup(void);
 
 // clext.c
@@ -30,6 +31,7 @@ int clext_get_displaystart(struct vgamode_s *vmode_g);
 int clext_set_displaystart(struct vgamode_s *vmode_g, int val);
 int clext_save_restore(int cmd, u16 seg, void *data);
 int clext_set_mode(struct vgamode_s *vmode_g, int flags);
+int clext_get_linesize(struct vgamode_s *vmode_g);
 struct bregs;
 void clext_1012(struct bregs *regs);
 int clext_setup(void);
@@ -63,6 +65,7 @@ void stdvga_list_modes(u16 seg, u16 *dest, u16 *last);
 void stdvga_build_video_param(void);
 void stdvga_override_crtc(int mode, u8 *crtc);
 int stdvga_set_mode(struct vgamode_s *vmode_g, int flags);
+int stdvga_get_linesize(struct vgamode_s *vmode_g);
 void stdvga_set_packed_palette(void);
 
 // swcursor.c
-- 
2.9.3