[SeaBIOS] [PATCH 07/15] vgabios: Unify page size calculations; remove page size from vgamode_s.
Kevin O'Connor
kevin at koconnor.net
Sat Jan 14 23:26:41 CET 2012
The previous code could obtain the page size in different ways - from
vmode_g->sslength, from SCREEN_MEM_START, or by manually multiplying
cols and rows. Add a new func (calc_page_size) and use that in areas
that need to calculate the page size.
Convert readers of the page size to read it from the "video_pagesize"
entry in the BDA instead of recalculating it.
Remove the page size from struct vgamode_s (slength) as it is now
calculated dynamically. The new calculated versions are different
from the existing values exported in video_param_table. However, the
existing values (for CGA) did not look correct - I compared the values
to those exported by two other VGA BIOS manufacturers and used the
values that look more standard.
Signed-off-by: Kevin O'Connor <kevin at koconnor.net>
---
vgasrc/stdvga.h | 1 -
vgasrc/vgabios.c | 53 +++++++++++++++++++++++++--------------------------
vgasrc/vgabios.h | 4 +--
vgasrc/vgafb.c | 20 +++++-------------
vgasrc/vgatables.c | 39 +++++++++++++++++++------------------
5 files changed, 53 insertions(+), 64 deletions(-)
diff --git a/vgasrc/stdvga.h b/vgasrc/stdvga.h
index 735022c..2aabf1b 100644
--- a/vgasrc/stdvga.h
+++ b/vgasrc/stdvga.h
@@ -53,7 +53,6 @@ struct vgamode_s {
u8 cwidth;
u8 cheight;
u16 sstart;
- u16 slength;
u8 pelmask;
u8 *dac;
diff --git a/vgasrc/vgabios.c b/vgasrc/vgabios.c
index 31636cc..854ed38 100644
--- a/vgasrc/vgabios.c
+++ b/vgasrc/vgabios.c
@@ -48,6 +48,19 @@ struct pci_data rom_pci_data VAR16VISIBLE = {
* Helper functions
****************************************************************/
+u16
+calc_page_size(u8 memmodel, u16 width, u16 height)
+{
+ switch (memmodel) {
+ case MM_TEXT:
+ return ALIGN(width * height * 2, 2*1024);
+ case MM_CGA:
+ return 16*1024;
+ default:
+ return ALIGN(width * height / 8, 8*1024);
+ }
+}
+
static void
set_cursor_shape(u8 start, u8 end)
{
@@ -93,15 +106,12 @@ set_cursor_pos(struct cursorpos cp)
if (cp.page != current)
return;
- // Get the dimensions
+ // Calculate the memory address
u16 nbcols = GET_BDA(video_cols);
- u16 nbrows = GET_BDA(video_rows) + 1;
+ u16 address = (GET_BDA(video_pagesize) * cp.page
+ + (cp.x + cp.y * nbcols) * 2);
- // Calculate the address knowing nbcols nbrows and page num
- u16 address = (SCREEN_IO_START(nbcols, nbrows, cp.page)
- + cp.x + cp.y * nbcols);
-
- stdvga_set_cursor_pos(address);
+ stdvga_set_cursor_pos(address / 2);
}
static struct cursorpos
@@ -134,25 +144,13 @@ set_active_page(u8 page)
// Get pos curs pos for the right page
struct cursorpos cp = get_cursor_pos(page);
- u16 address;
- if (GET_GLOBAL(vmode_g->memmodel) == MM_TEXT) {
- // Get the dimensions
- u16 nbcols = GET_BDA(video_cols);
- u16 nbrows = GET_BDA(video_rows) + 1;
-
- // Calculate the address knowing nbcols nbrows and page num
- address = SCREEN_MEM_START(nbcols, nbrows, page);
- SET_BDA(video_pagestart, address);
-
- // Start address
- address = SCREEN_IO_START(nbcols, nbrows, page);
- } else {
- address = page * GET_GLOBAL(vmode_g->slength);
- }
-
- stdvga_set_active_page(address);
+ // Calculate memory address of start of page
+ u8 memmodel = GET_GLOBAL(vmode_g->memmodel);
+ u16 address = GET_BDA(video_pagesize) * page;
+ stdvga_set_active_page(memmodel == MM_TEXT ? address / 2 : address);
// And change the BIOS page
+ SET_BDA(video_pagestart, address);
SET_BDA(video_page, page);
dprintf(1, "Set active page %02x address %04x\n", page, address);
@@ -174,7 +172,7 @@ set_scan_lines(u8 lines)
u8 rows = vde / lines;
SET_BDA(video_rows, rows - 1);
u16 cols = GET_BDA(video_cols);
- SET_BDA(video_pagesize, rows * cols * 2);
+ SET_BDA(video_pagesize, calc_page_size(MM_TEXT, cols, rows));
}
@@ -331,9 +329,10 @@ modeswitch_set_bda(int mode, int flags, struct vgamode_s *vmode_g)
// Set the BIOS mem
int width = GET_GLOBAL(vmode_g->width);
int height = GET_GLOBAL(vmode_g->height);
+ u8 memmodel = GET_GLOBAL(vmode_g->memmodel);
int cheight = GET_GLOBAL(vmode_g->cheight);
SET_BDA(video_mode, mode);
- if (GET_GLOBAL(vmode_g->memmodel) == MM_TEXT) {
+ if (memmodel == MM_TEXT) {
SET_BDA(video_cols, width);
SET_BDA(video_rows, height-1);
SET_BDA(cursor_type, 0x0607);
@@ -343,7 +342,7 @@ modeswitch_set_bda(int mode, int flags, struct vgamode_s *vmode_g)
SET_BDA(video_rows, (height / cheight) - 1);
SET_BDA(cursor_type, 0x0000);
}
- SET_BDA(video_pagesize, GET_GLOBAL(vmode_g->slength));
+ SET_BDA(video_pagesize, calc_page_size(memmodel, width, height));
SET_BDA(crtc_address, stdvga_get_crtc());
SET_BDA(char_height, cheight);
SET_BDA(video_ctl, 0x60 | (flags & MF_NOCLEARMEM ? 0x80 : 0x00));
diff --git a/vgasrc/vgabios.h b/vgasrc/vgabios.h
index 7c5e8d3..8b806ff 100644
--- a/vgasrc/vgabios.h
+++ b/vgasrc/vgabios.h
@@ -4,9 +4,6 @@
#include "types.h" // u8
#include "farptr.h" // struct segoff_s
-#define SCREEN_IO_START(x,y,p) (((((x)*(y)) | 0x00ff) + 1) * (p))
-#define SCREEN_MEM_START(x,y,p) SCREEN_IO_START(((x)*2),(y),(p))
-
struct saveBDAstate {
u8 video_mode;
u16 video_cols;
@@ -66,6 +63,7 @@ struct carattr {
struct cursorpos {
u8 x, y, page;
};
+u16 calc_page_size(u8 memmodel, u16 width, u16 height);
void modeswitch_set_bda(int mode, int flags, struct vgamode_s *vmode_g);
// vgafb.c
diff --git a/vgasrc/vgafb.c b/vgasrc/vgafb.c
index eb4ced8..b933738 100644
--- a/vgasrc/vgafb.c
+++ b/vgasrc/vgafb.c
@@ -139,10 +139,8 @@ scroll_text(struct vgamode_s *vmode_g, int nblines, int attr
{
int cheight = 1;
int cwidth = 2;
- u16 nbrows = GET_BDA(video_rows) + 1;
- u16 nbcols = GET_BDA(video_cols);
- int stride = nbcols * cwidth;
- void *src_far, *dest_far = (void*)SCREEN_MEM_START(nbcols, nbrows, ul.page);
+ int stride = GET_BDA(video_cols) * cwidth;
+ void *src_far, *dest_far = (void*)(GET_BDA(video_pagesize) * ul.page);
if (nblines >= 0) {
dest_far += ul.y * cheight * stride + ul.x * cwidth;
src_far = dest_far + nblines * cheight * stride;
@@ -330,12 +328,9 @@ static void
write_text_char(struct vgamode_s *vmode_g
, struct cursorpos cp, struct carattr ca)
{
- // Get the dimensions
- u16 nbrows = GET_BDA(video_rows) + 1;
- u16 nbcols = GET_BDA(video_cols);
-
// Compute the address
- void *address_far = (void*)(SCREEN_MEM_START(nbcols, nbrows, cp.page)
+ u16 nbcols = GET_BDA(video_cols);
+ void *address_far = (void*)(GET_BDA(video_pagesize) * cp.page
+ (cp.x + cp.y * nbcols) * 2);
if (ca.use_attr) {
@@ -386,12 +381,9 @@ vgafb_read_char(struct cursorpos cp)
goto fail;
}
- // Get the dimensions
- u16 nbrows = GET_BDA(video_rows) + 1;
- u16 nbcols = GET_BDA(video_cols);
-
// Compute the address
- u16 *address_far = (void*)(SCREEN_MEM_START(nbcols, nbrows, cp.page)
+ u16 nbcols = GET_BDA(video_cols);
+ u16 *address_far = (void*)(GET_BDA(video_pagesize) * cp.page
+ (cp.x + cp.y * nbcols) * 2);
u16 v = GET_FARVAR(GET_GLOBAL(vmode_g->sstart), *address_far);
struct carattr ca = {v, v>>8, 0};
diff --git a/vgasrc/vgatables.c b/vgasrc/vgatables.c
index 314222e..4fd9964 100644
--- a/vgasrc/vgatables.c
+++ b/vgasrc/vgatables.c
@@ -63,8 +63,9 @@ build_video_param(void)
continue;
int width = GET_GLOBAL(vmode_g->width);
int height = GET_GLOBAL(vmode_g->height);
+ u8 memmodel = GET_GLOBAL(vmode_g->memmodel);
int cheight = GET_GLOBAL(vmode_g->cheight);
- if (GET_GLOBAL(vmode_g->memmodel) == MM_TEXT) {
+ if (memmodel == MM_TEXT) {
SET_VGA(vparam_g->twidth, width);
SET_VGA(vparam_g->theightm1, height-1);
} else {
@@ -73,7 +74,7 @@ build_video_param(void)
SET_VGA(vparam_g->theightm1, (height / cheight) - 1);
}
SET_VGA(vparam_g->cheight, cheight);
- SET_VGA(vparam_g->slength, GET_GLOBAL(vmode_g->slength));
+ SET_VGA(vparam_g->slength, calc_page_size(memmodel, width, height));
memcpy_far(get_global_seg(), vparam_g->sequ_regs
, get_global_seg(), GET_GLOBAL(vmode_g->sequ_regs)
, ARRAY_SIZE(vparam_g->sequ_regs));
@@ -346,39 +347,39 @@ static u8 crtc_6A[] VAR16 = {
#define VPARAM(x) &video_param_table[x]
static struct vgamode_s vga_modes[] VAR16 = {
- //mode model tx ty bpp cw ch sstart slength
+ //mode model tx ty bpp cw ch sstart
// pelm dac sequ misc crtc actl grdc
- {0x00, MM_TEXT, 40, 25, 4, 9, 16, SEG_CTEXT, 0x0800
+ {0x00, MM_TEXT, 40, 25, 4, 9, 16, SEG_CTEXT
, 0xFF, PAL(palette2), sequ_01, 0x67, crtc_01, actl_01, grdc_01},
- {0x01, MM_TEXT, 40, 25, 4, 9, 16, SEG_CTEXT, 0x0800
+ {0x01, MM_TEXT, 40, 25, 4, 9, 16, SEG_CTEXT
, 0xFF, PAL(palette2), sequ_01, 0x67, crtc_01, actl_01, grdc_01},
- {0x02, MM_TEXT, 80, 25, 4, 9, 16, SEG_CTEXT, 0x1000
+ {0x02, MM_TEXT, 80, 25, 4, 9, 16, SEG_CTEXT
, 0xFF, PAL(palette2), sequ_03, 0x67, crtc_03, actl_01, grdc_01},
- {0x03, MM_TEXT, 80, 25, 4, 9, 16, SEG_CTEXT, 0x1000
+ {0x03, MM_TEXT, 80, 25, 4, 9, 16, SEG_CTEXT
, 0xFF, PAL(palette2), sequ_03, 0x67, crtc_03, actl_01, grdc_01},
- {0x04, MM_CGA, 320, 200, 2, 8, 8, SEG_CTEXT, 0x0800
+ {0x04, MM_CGA, 320, 200, 2, 8, 8, SEG_CTEXT
, 0xFF, PAL(palette1), sequ_04, 0x63, crtc_04, actl_04, grdc_04},
- {0x05, MM_CGA, 320, 200, 2, 8, 8, SEG_CTEXT, 0x0800
+ {0x05, MM_CGA, 320, 200, 2, 8, 8, SEG_CTEXT
, 0xFF, PAL(palette1), sequ_04, 0x63, crtc_04, actl_04, grdc_04},
- {0x06, MM_CGA, 640, 200, 1, 8, 8, SEG_CTEXT, 0x1000
+ {0x06, MM_CGA, 640, 200, 1, 8, 8, SEG_CTEXT
, 0xFF, PAL(palette1), sequ_06, 0x63, crtc_06, actl_06, grdc_06},
- {0x07, MM_TEXT, 80, 25, 4, 9, 16, SEG_MTEXT, 0x1000
+ {0x07, MM_TEXT, 80, 25, 4, 9, 16, SEG_MTEXT
, 0xFF, PAL(palette0), sequ_03, 0x66, crtc_07, actl_07, grdc_07},
- {0x0D, MM_PLANAR, 320, 200, 4, 8, 8, SEG_GRAPH, 0x2000
+ {0x0D, MM_PLANAR, 320, 200, 4, 8, 8, SEG_GRAPH
, 0xFF, PAL(palette1), sequ_0d, 0x63, crtc_0d, actl_0d, grdc_0d},
- {0x0E, MM_PLANAR, 640, 200, 4, 8, 8, SEG_GRAPH, 0x4000
+ {0x0E, MM_PLANAR, 640, 200, 4, 8, 8, SEG_GRAPH
, 0xFF, PAL(palette1), sequ_0e, 0x63, crtc_0e, actl_0d, grdc_0d},
- {0x0F, MM_PLANAR, 640, 350, 1, 8, 14, SEG_GRAPH, 0x8000
+ {0x0F, MM_PLANAR, 640, 350, 1, 8, 14, SEG_GRAPH
, 0xFF, PAL(palette0), sequ_0e, 0xa3, crtc_0f, actl_0f, grdc_0d},
- {0x10, MM_PLANAR, 640, 350, 4, 8, 14, SEG_GRAPH, 0x8000
+ {0x10, MM_PLANAR, 640, 350, 4, 8, 14, SEG_GRAPH
, 0xFF, PAL(palette2), sequ_0e, 0xa3, crtc_0f, actl_10, grdc_0d},
- {0x11, MM_PLANAR, 640, 480, 1, 8, 16, SEG_GRAPH, 0x0000
+ {0x11, MM_PLANAR, 640, 480, 1, 8, 16, SEG_GRAPH
, 0xFF, PAL(palette2), sequ_0e, 0xe3, crtc_11, actl_11, grdc_0d},
- {0x12, MM_PLANAR, 640, 480, 4, 8, 16, SEG_GRAPH, 0x0000
+ {0x12, MM_PLANAR, 640, 480, 4, 8, 16, SEG_GRAPH
, 0xFF, PAL(palette2), sequ_0e, 0xe3, crtc_11, actl_10, grdc_0d},
- {0x13, MM_PACKED, 320, 200, 8, 8, 8, SEG_GRAPH, 0x0000
+ {0x13, MM_PACKED, 320, 200, 8, 8, 8, SEG_GRAPH
, 0xFF, PAL(palette3), sequ_13, 0x63, crtc_13, actl_13, grdc_13},
- {0x6A, MM_PLANAR, 800, 600, 4, 8, 16, SEG_GRAPH, 0x0000
+ {0x6A, MM_PLANAR, 800, 600, 4, 8, 16, SEG_GRAPH
, 0xFF, PAL(palette2), sequ_0e, 0xe3, crtc_6A, actl_10, grdc_0d},
};
--
1.7.6.4
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