From 72df91d99ba7e9a032d6cb171571e075d0f6ce53 Mon Sep 17 00:00:00 2001
From: Freya Murphy <freya@freyacat.org>
Date: Fri, 2 Feb 2024 16:41:19 -0500
Subject: [PATCH] pretty colors

---
 Makefile             |  2 +-
 grub.cfg             |  2 ++
 include/fpu.h        |  3 +++
 src/arch/amd64/fb.c  | 28 +++++++++++++++++++++++++++-
 src/arch/amd64/fpu.c | 12 ++++++++++++
 src/arch/amd64/pci.c |  6 ++++--
 src/kmain.c          |  2 ++
 7 files changed, 51 insertions(+), 4 deletions(-)
 create mode 100644 include/fpu.h
 create mode 100644 src/arch/amd64/fpu.c

diff --git a/Makefile b/Makefile
index 19b2342..d8ab7a8 100644
--- a/Makefile
+++ b/Makefile
@@ -55,7 +55,7 @@ run: all
 	@qemu-system-x86_64 \
 		-cdrom build/$(ISO) \
 		-serial stdio \
-		-display gtk,show-menubar=off,zoom-to-fit=on \
+		-display sdl \
 		-m 1G \
 		-enable-kvm \
 		-name corn
diff --git a/grub.cfg b/grub.cfg
index 3aa3a12..d34c818 100644
--- a/grub.cfg
+++ b/grub.cfg
@@ -1,5 +1,7 @@
 set timeout=1
 set default=0
+terminal_input at_keyboard
+termianl_output console
 
 menuentry "corn" {
 	multiboot2 /boot/kernel.bin
diff --git a/include/fpu.h b/include/fpu.h
new file mode 100644
index 0000000..88dfe47
--- /dev/null
+++ b/include/fpu.h
@@ -0,0 +1,3 @@
+#pragma once
+
+void enable_fpu();
diff --git a/src/arch/amd64/fb.c b/src/arch/amd64/fb.c
index ab15dd6..8484f29 100644
--- a/src/arch/amd64/fb.c
+++ b/src/arch/amd64/fb.c
@@ -3,6 +3,7 @@
 #include <serial.h>
 #include <stdint.h>
 #include <panic.h>
+#include <pci.h>
 
 #include "bindings.h"
 
@@ -25,6 +26,9 @@
 #define DATA_LFB_ENABLE     0x40
 #define DATA_NO_CLEAR_MEM   0x80
 
+#define BOCHS_PCI_VENDOR    0x1234
+#define BOCHS_PCI_DEVICE    0x1111
+
 static void write(uint16_t index, uint16_t data) {
     outw(INDEX, index);
     outw(DATA, data);
@@ -60,5 +64,27 @@ int fb_init(uint16_t width, uint16_t height) {
 	if (!is_available())
 		panic("bochs framebuffer not avaliable");
 
-	return 0;
+    struct pci_device bochs = {0};
+    bool found = pci_findby_id(&bochs, BOCHS_PCI_DEVICE, BOCHS_PCI_VENDOR, NULL);
+    if (!found)
+        panic("bochs pci device not avaliable");
+
+    uint32_t bar0 = pci_rcfg_d(bochs, PCI_BAR0_D);
+    uint32_t *fb = (uint32_t*) (uintptr_t) bar0;
+    fb = mmap(fb, width * height * 4);
+
+	for (uint16_t y = 0; y < height; y++) {
+		for (uint16_t x = 0; x < width; x++) {
+            double dx = x / (double) width,
+                   dy = y / (double) height,
+                   dz = (2 - dx - dy) / 2;
+            uint32_t r = (uint32_t)(dx * 255),
+                     g = (uint32_t)(dy * 255),
+                     b = (uint32_t)(dz * 255);
+			fb[x + y * width] = (b << 0) | (g << 8) | (r << 16);
+		}
+	}
+
+
+    return 0;
 }
diff --git a/src/arch/amd64/fpu.c b/src/arch/amd64/fpu.c
new file mode 100644
index 0000000..551485e
--- /dev/null
+++ b/src/arch/amd64/fpu.c
@@ -0,0 +1,12 @@
+#include <fpu.h>
+#include <stddef.h>
+#include <stdint.h>
+
+void enable_fpu() {
+	size_t cr4;
+	uint16_t cw = 0x37F;
+	__asm__ volatile ("mov %%cr4, %0" : "=r"(cr4));
+	cr4 |= 0x200;
+	__asm__ volatile ("mov %0, %%cr4" :: "r"(cr4));
+	__asm__ volatile("fldcw %0" :: "m"(cw));
+}
diff --git a/src/arch/amd64/pci.c b/src/arch/amd64/pci.c
index 0deac03..7b30f0e 100644
--- a/src/arch/amd64/pci.c
+++ b/src/arch/amd64/pci.c
@@ -102,12 +102,10 @@ static struct pci_table_entry *load_device(struct pci_device dev) {
 	entry->prog_if = (dword2 >> 8) & 0xFF;
 	entry->revision = dword2 & 0xFF;
 
-	print_device(entry);
 	return entry;
 }
 
 void pci_init(void) {
-	kprintf("PCI DEVICES\n");
 	pci_table_next = 0;
 	struct pci_device pcidev;
 	for(int bus = 0; bus < 256; bus++) {
@@ -134,6 +132,10 @@ void pci_init(void) {
 			}
 		}
 	}
+	kprintf("PCI DEVICES\n");
+	for (size_t i = 0; i < pci_table_next; i++) {
+		print_device(&pci_table[i]);
+	}
 	kprintf("\n");
 }
 
diff --git a/src/kmain.c b/src/kmain.c
index 476bcdc..bc1d225 100644
--- a/src/kmain.c
+++ b/src/kmain.c
@@ -1,3 +1,4 @@
+#include "fpu.h"
 #include <acpi.h>
 #include <memory.h>
 #include <lib.h>
@@ -8,6 +9,7 @@
 #include <pci.h>
 
 void kmain(struct boot_info *info) {
+	enable_fpu();
 	memory_init(&info->map);
 	pci_init();
 	fb_init(1024, 768);