[SeaBIOS] Cirrus VGA driver work
Kevin O'Connor
kevin at koconnor.net
Mon Dec 19 05:48:14 CET 2011
I was reviewing some of my past work on the Cirrus VGA BIOS port. I
rechecked the work and figured I'd post what I had. The code is
completely untested.
What makes this interesting, though, is that the Cirrus driver is only
really lacking VBE support after this. With Julian's recent work,
maybe Cirrus support isn't far off.
-Kevin
diff --git a/vgasrc/clext.c b/vgasrc/clext.c
index 36ccad3..225292e 100644
--- a/vgasrc/clext.c
+++ b/vgasrc/clext.c
@@ -9,6 +9,11 @@
#include "biosvar.h" // GET_GLOBAL
#include "util.h" // dprintf
+
+/****************************************************************
+ * tables
+ ****************************************************************/
+
struct cirrus_mode_s {
/* + 0 */
u16 mode;
@@ -289,6 +294,11 @@ static struct cirrus_mode_s cirrus_modes[] VAR16 = {
0xff,0,0,0,0,0,0,0,0},
};
+
+/****************************************************************
+ * helper functions
+ ****************************************************************/
+
static struct cirrus_mode_s *
cirrus_get_modeentry(u8 mode)
{
@@ -348,19 +358,63 @@ cirrus_switch_mode(struct cirrus_mode_s *table)
vgahw_set_single_palette_reg(0x10, v);
}
-void
+static u8
+cirrus_get_memsize(void)
+{
+ // get DRAM band width
+ outb(0x0f, VGAREG_SEQU_ADDRESS);
+ u8 v = inb(VGAREG_SEQU_DATA);
+ u8 x = (v >> 3) & 0x03;
+ if (x == 0x03) {
+ if (v & 0x80)
+ // 4MB
+ return 0x40;
+ // 2MB
+ return 0x20;
+ }
+ return 0x04 << x;
+}
+
+static void
+cirrus_enable_16k_granularity(void)
+{
+ outb(0x0b, VGAREG_GRDC_ADDRESS);
+ u8 v = inb(VGAREG_GRDC_DATA);
+ outb(v | 0x20, VGAREG_GRDC_DATA);
+}
+
+static void
+cirrus_clear_vram(u16 param)
+{
+ cirrus_enable_16k_granularity();
+ u8 count = cirrus_get_memsize() * 4;
+ u8 i;
+ for (i=0; i<count; i++) {
+ outw((i<<8) | 0x09, VGAREG_GRDC_ADDRESS);
+ memset16_far(0xa000, (void*)0, param, 16 * 1024);
+ }
+ outw(0x0009, VGAREG_GRDC_ADDRESS);
+}
+
+int
cirrus_set_video_mode(u8 mode)
{
dprintf(1, "cirrus mode %d\n", mode);
SET_BDA(vbe_mode, 0);
struct cirrus_mode_s *table_g = cirrus_get_modeentry(mode & 0x7f);
if (table_g) {
- //XXX - cirrus_set_video_mode_extended(table);
- return;
+ cirrus_switch_mode(table_g);
+ // XXX - pass in mode without 0x7f mask
+ if (mode & 0x80)
+ cirrus_clear_vram(0xffff);
+ SET_BDA(video_mode, mode & 0x7f);
+ // XXX - return early from caller.
+ return 0;
}
table_g = cirrus_get_modeentry(0xfe);
cirrus_switch_mode(table_g);
dprintf(1, "cirrus mode switch regular\n");
+ return -1;
}
static int
@@ -370,6 +424,243 @@ cirrus_check(void)
return inb(VGAREG_SEQU_DATA) == 0x12;
}
+
+/****************************************************************
+ * extbios
+ ****************************************************************/
+
+static void
+cirrus_extbios_80h(struct bregs *regs)
+{
+ u16 crtc_addr = cirrus_get_crtc();
+ outb(0x27, crtc_addr);
+ u8 v = inb(crtc_addr + 1);
+ if (v == 0xa0)
+ // 5430
+ regs->ax = 0x0032;
+ else if (v == 0xb8)
+ // 5446
+ regs->ax = 0x0039;
+ else
+ regs->ax = 0x00ff;
+ regs->bx = 0x00;
+ return;
+}
+
+static void
+cirrus_extbios_81h(struct bregs *regs)
+{
+ // XXX
+ regs->ax = 0x0100;
+}
+
+static void
+cirrus_extbios_82h(struct bregs *regs)
+{
+ u16 crtc_addr = cirrus_get_crtc();
+ outb(0x27, crtc_addr);
+ regs->al = inb(crtc_addr + 1) & 0x03;
+ regs->ah = 0xAF;
+}
+
+static void
+cirrus_extbios_85h(struct bregs *regs)
+{
+ regs->al = cirrus_get_memsize();
+}
+
+static void
+cirrus_extbios_9Ah(struct bregs *regs)
+{
+ regs->ax = 0x4060;
+ regs->cx = 0x1132;
+}
+
+extern void a0h_callback(void);
+ASM16(
+ // fatal: not implemented yet
+ "a0h_callback:"
+ "cli\n"
+ "hlt\n"
+ "retf");
+
+static void
+cirrus_extbios_A0h(struct bregs *regs)
+{
+ struct cirrus_mode_s *table_g = cirrus_get_modeentry(regs->al & 0x7f);
+ regs->ah = (table_g ? 1 : 0);
+ regs->si = 0xffff;
+ regs->di = regs->ds = regs->es = regs->bx = (u32)a0h_callback;
+}
+
+static void
+cirrus_extbios_A1h(struct bregs *regs)
+{
+ regs->bx = 0x0e00; // IBM 8512/8513, color
+}
+
+static void
+cirrus_extbios_A2h(struct bregs *regs)
+{
+ regs->al = 0x07; // HSync 31.5 - 64.0 kHz
+}
+
+static void
+cirrus_extbios_AEh(struct bregs *regs)
+{
+ regs->al = 0x01; // High Refresh 75Hz
+}
+
+void
+cirrus_extbios(struct bregs *regs)
+{
+ // XXX - regs->bl < 0x80 or > 0xaf call regular handlers.
+ switch (regs->bl) {
+ case 0x80: cirrus_extbios_80h(regs); break;
+ case 0x81: cirrus_extbios_81h(regs); break;
+ case 0x82: cirrus_extbios_82h(regs); break;
+ case 0x85: cirrus_extbios_85h(regs); break;
+ case 0x9a: cirrus_extbios_9Ah(regs); break;
+ case 0xa0: cirrus_extbios_A0h(regs); break;
+ case 0xa1: cirrus_extbios_A1h(regs); break;
+ case 0xa2: cirrus_extbios_A2h(regs); break;
+ case 0xae: cirrus_extbios_AEh(regs); break;
+ default: break;
+ }
+}
+
+
+/****************************************************************
+ * vesa calls
+ ****************************************************************/
+
+#if 0
+static u16
+cirrus_vesamode_to_mode(u16 vesamode)
+{
+ // XXX - convert assembler
+ return 0;
+}
+
+static u8
+cirrus_get_bpp_bytes(void)
+{
+ // XXX - convert assembler
+ return 0;
+}
+
+static void
+cirrus_set_line_offset(u16 new_line_offset)
+{
+ // XXX - convert assembler
+}
+
+static u16
+cirrus_get_line_offset(void)
+{
+ // XXX - convert assembler
+ return 0;
+}
+
+static u16
+cirrus_get_line_offset_entry(void *table)
+{
+ // XXX - convert assembler
+ return 0;
+}
+
+static void
+cirrus_set_start_addr(void *addr)
+{
+ // XXX - convert assembler
+}
+
+static void *
+cirrus_get_start_addr(void)
+{
+ // XXX - convert assembler
+ return NULL;
+}
+#endif
+
+static void
+cirrus_vesa_00h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_01h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_02h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_03h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+// XXX - add cirrus_vesa_05h_farentry to vgaentry.S
+
+static void
+cirrus_vesa_05h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_06h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_07h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_10h(struct bregs *regs)
+{
+ // XXX - convert assembler
+}
+
+static void
+cirrus_vesa_not_handled(struct bregs *regs)
+{
+ debug_stub(regs);
+ regs->ax = 0x014f;
+}
+
+void
+cirrus_vesa(struct bregs *regs)
+{
+ switch (regs->al) {
+ case 0x00: cirrus_vesa_00h(regs); break;
+ case 0x01: cirrus_vesa_01h(regs); break;
+ case 0x02: cirrus_vesa_02h(regs); break;
+ case 0x03: cirrus_vesa_03h(regs); break;
+ case 0x05: cirrus_vesa_05h(regs); break;
+ case 0x06: cirrus_vesa_06h(regs); break;
+ case 0x07: cirrus_vesa_07h(regs); break;
+ case 0x10: cirrus_vesa_10h(regs); break;
+ default: cirrus_vesa_not_handled(regs); break;
+ }
+}
+
+
+/****************************************************************
+ * init
+ ****************************************************************/
+
void
cirrus_init(void)
{
diff --git a/vgasrc/vgatables.h b/vgasrc/vgatables.h
index 1e76b3a..48bf828 100644
--- a/vgasrc/vgatables.h
+++ b/vgasrc/vgatables.h
@@ -205,7 +205,7 @@ void vgahw_enable_video_addressing(u8 disable);
void vgahw_init(void);
// clext.c
-void cirrus_set_video_mode(u8 mode);
+int cirrus_set_video_mode(u8 mode);
void cirrus_init(void);
// vbe.c -- not implemented yet.
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