font rending in framebuffer yay!!

1 files changed, 98 insertions, 0 deletions

diff --git a/kernel/drivers/gpu/bochs.c b/kernel/drivers/gpu/bochs.c
new file mode 100644
index 0000000..5b0f1fc
--- /dev/null
+++ b/kernel/drivers/gpu/bochs.c
@@ -0,0 +1,98 @@
+#include <lib.h>
+#include <comus/asm.h>
+#include <comus/memory.h>
+#include <comus/drivers/pci.h>
+#include <comus/drivers/gpu/bochs.h>
+
+#define INDEX           0x1CE
+#define DATA            0x1CF
+
+#define INDEX_ID            0
+#define INDEX_XRES          1
+#define INDEX_YRES          2
+#define INDEX_BPP           3
+#define INDEX_ENABLE        4
+#define INDEX_BANK          5
+#define INDEX_VIRT_WIDTH    6
+#define INDEX_VIRT_HEIGHT   7
+#define INDEX_X_OFFSET      8
+#define INDEX_Y_OFFSET      9
+
+#define DATA_DISP_DISABLE   0x00
+#define DATA_DISP_ENABLE    0x01
+#define DATA_LFB_ENABLE     0x40
+#define DATA_NO_CLEAR_MEM   0x80
+
+#define BOCHS_PCI_VENDOR    0x1234
+#define BOCHS_PCI_DEVICE    0x1111
+
+#define BOCHS_WIDTH 1024
+#define BOCHS_HEIGHT 768
+#define BOCHS_BIT_DEPTH 32
+
+static volatile uint32_t *framebuffer;
+static uint16_t width = BOCHS_WIDTH;
+static uint16_t height = BOCHS_HEIGHT;
+static uint8_t bit_depth = BOCHS_BIT_DEPTH;
+
+static void write(uint16_t index, uint16_t data) {
+	outw(INDEX, index);
+	outw(DATA, data);
+}
+
+static uint16_t read(uint16_t value) {
+	outw(INDEX, value);
+	return inw(DATA);
+}
+
+static int is_available(void) {
+	return (read(INDEX_ID) == 0xB0C5);
+}
+
+static void set_mode(uint16_t width, uint16_t height, uint16_t bit_depth, int lfb, int clear) {
+	write(INDEX_ENABLE, DATA_DISP_DISABLE);
+	write(INDEX_XRES, width);
+	write(INDEX_YRES, height);
+	write(INDEX_BPP, bit_depth);
+	write(INDEX_ENABLE, DATA_DISP_ENABLE |
+			(lfb ? DATA_LFB_ENABLE : 0) |
+			(clear ? 0 : DATA_NO_CLEAR_MEM));
+}
+
+int bochs_init(void) {
+	struct pci_device bochs = {0};
+	bool found = pci_findby_id(&bochs, BOCHS_PCI_DEVICE, BOCHS_PCI_VENDOR, NULL);
+	if (!found)
+		return 1;
+
+	set_mode(width, height, bit_depth, true, true);
+	if (!is_available())
+		return 1;
+
+	uint32_t bar0 = pci_rcfg_d(bochs, PCI_BAR0_D);
+	uint32_t *addr = (uint32_t *) (uintptr_t) bar0;
+	framebuffer = kmapaddr(addr, NULL, width * height * bit_depth, F_WRITEABLE);
+
+	return 0;
+}
+
+uint32_t bochs_width(void)
+{
+	return width;
+}
+
+uint32_t bochs_height(void)
+{
+	return height;
+}
+
+uint8_t bochs_bit_depth(void)
+{
+	return bit_depth;
+}
+
+void bochs_set_pixel(uint32_t x, uint32_t y, uint32_t r, uint32_t g, uint32_t b)
+{
+	uint32_t index = x + y * width;
+	framebuffer[index] = (b << 0) | (g << 8) | (r << 16);
+}