Framebuffer rendering, x86 serial fix

include/menix/log.h

@@ -8,8 +8,9 @@
 #define kassert(expr, msg) \
 	if (!(expr)) \
 	{ \
-		kmesg("Assertion failed: " msg "\nExpression:\n\t" #expr "\n" __FILE__ ":" __PASTE_STR(__LINE__) "\n"); \
+		kmesg("Assertion failed: " msg "\nExpression:\n    " #expr "\n" __FILE__ ":" __PASTE_STR(__LINE__) "\n"); \
 		ktrace(); \
+		kabort(); \
 	}
 
 typedef struct ATTR(packed) StackFrame

include/menix/video/fb.h

@@ -30,7 +30,7 @@ typedef struct
 	u32 width, height;						// Resolution of the visible frame in pixels.
 	u32 v_width, v_height;					// Resolution of the virtual frame in pixels.
 	u32 v_off_x, v_off_y;					// Offset from virtual to visible resolution.
-	u8 bpp;									// Amount of bits per pixel.
+	u8 cpp;									// Amount of bytes per pixel.
 	FbColorBits red, green, blue, alpha;	// Bitfields for each part of a pixel.
 } FbModeInfo;
 
@@ -50,6 +50,14 @@ typedef struct
 	u32 width, height;	  // Width and height of the area to copy.
 } FbCopyRegion;
 
+// Arguments passed to `FbFuncs.draw_region`.
+typedef struct
+{
+	u32 x_src, y_src;	  // Top left corner of the framebuffer to draw to.
+	u32 width, height;	  // Width and height of the image to draw.
+	const u8* data;		  // Pointer to the image data.
+} FbDrawRegion;
+
 typedef struct FrameBuffer FrameBuffer;
 // Callback functions for modifying a framebuffer.
 typedef struct
@@ -64,6 +72,8 @@ typedef struct
 	void (*fill_region)(FrameBuffer* fb, FbFillRegion* args);
 	// Copies a rectangular region from one location to another.
 	void (*copy_region)(FrameBuffer* fb, FbCopyRegion* args);
+	// Draws an image to a location.
+	void (*draw_region)(FrameBuffer* fb, FbDrawRegion* args);
 } FbFuncs;
 
 // Stores information about a framebuffer.

include/menix/video/fb_default.h

@@ -3,6 +3,6 @@
 #pragma once
 #include <menix/video/fb.h>
 
-#define FB_DEFAULT_FUNCS \
-	{ \
-	}
+void fb_default_fill_region(FrameBuffer* fb, FbFillRegion* args);
+void fb_default_copy_region(FrameBuffer* fb, FbCopyRegion* args);
+void fb_default_draw_region(FrameBuffer* fb, FbDrawRegion* args);

kernel/arch/x86/arch.c

@@ -21,18 +21,6 @@ void arch_early_init()
 
 void arch_init(BootInfo* info)
 {
-	// Initialize physical and virtual memory managers.
-	pm_init(info->phys_map, info->memory_map, info->mm_num);
-	vm_init(info->phys_map, info->kernel_phys, info->memory_map, info->mm_num);
-
-	// Print memory map.
-	kmesg("Physical memory map:\n");
-	for (usize i = 0; i < info->mm_num; i++)
-	{
-		kmesg("    [%u] 0x%p - 0x%p [%s]\n", i, info->memory_map[i].address,
-			  info->memory_map[i].address + info->memory_map[i].length,
-			  (info->memory_map[i].usage == PhysMemoryUsage_Free) ? "Usable" : "Reserved");
-	}
 }
 
 void arch_shutdown(BootInfo* info)

kernel/arch/x86/io/serial.c

@@ -17,6 +17,9 @@
 
 #define TRANSMIT_FREE (arch_x86_read8(COM1_BASE + LINE_STATUS_REG) & 0x20)
 
+// If the COM port works or not.
+static bool can_use_serial = false;
+
 void serial_initialize()
 {
 	arch_x86_write8(COM1_BASE + INT_ENABLE_REG, 0x00);			// Disable interrupts
@@ -26,13 +29,25 @@ void serial_initialize()
 	arch_x86_write8(COM1_BASE + LINE_CTRL_REG, 0x03);			// 8 bits, no parity, one stop bit
 	arch_x86_write8(COM1_BASE + INT_ID_FIFO_CTRL_REG, 0xC7);	// Enable FIFO, clear them, with 14-byte threshold
 	arch_x86_write8(COM1_BASE + MODEM_CTRL_REG, 0x0B);			// IRQs enabled, RTS/DSR set
+	arch_x86_write8(COM1_BASE + MODEM_CTRL_REG, 0x1E);			// Set to loopback mode for testing.
+
+	arch_x86_write8(COM1_BASE + DATA_REG, 0xAE);		 // Send a test byte.
+	if (arch_x86_read8(COM1_BASE + DATA_REG) == 0xAE)	 // If we get the same back, we're ready.
+	{
+		can_use_serial = true;
+		arch_x86_write8(COM1_BASE + MODEM_CTRL_REG, 0x0F);	  // Set back to normal operation mode.
+	}
 }
 
 void serial_putchar(char c)
 {
-	// Wait for transmit to be empty.
+	if (!can_use_serial)
+		return;
+
+	// Wait until we can send things.
 	while (TRANSMIT_FREE == false)
 		;
+
 	switch (c)
 	{
 		case '\0': break;	 // Don't transmit null terminators.

kernel/arch/x86/vm.c

@@ -47,8 +47,17 @@ void vm_init(void* phys_base, PhysAddr kernel_base, PhysMemory* mem_map, usize n
 
 	// TODO: We could probably pre-allocate the upper half of pages, i.e. index 256..511
 
-	// Map the lower 256 GiB of physical space.
-	for (usize cur = 0; cur < 256UL * GiB; cur += 2UL * MiB)
+	// Map all physical space.
+	// Check for the highest usable physical memory address, so we know how much memory to map.
+	usize highest = 0;
+	for (usize i = 0; i < num_entries; i++)
+	{
+		const usize region_end = mem_map[i].address + mem_map[i].length;
+		if (region_end > highest)
+			highest = region_end;
+	}
+
+	for (usize cur = 0; cur < highest; cur += 2UL * MiB)
 		kassert(vm_arch_map_page(kernel_map, cur, phys_addr + cur, PAGE_PRESENT | PAGE_READ_WRITE, PageSize_2MiB),
 				"Unable to map lower memory!\n");
 

kernel/boot/boot_limine/limine_entry.c

@@ -13,7 +13,7 @@
 #include <string.h>
 
 #include "limine.h"
-#include "menix/video/fb.h"
+#include "menix/video/fb_default.h"
 
 #define LIMINE_REQUEST(request, tag, rev) \
 	ATTR(used, section(".requests")) static volatile struct limine_##request request = { \
@@ -30,7 +30,7 @@ LIMINE_REQUEST(memmap_request, LIMINE_MEMMAP_REQUEST, 0);					 // Get memory map
 LIMINE_REQUEST(hhdm_request, LIMINE_HHDM_REQUEST, 0);						 // Directly map 32-bit physical space.
 LIMINE_REQUEST(kernel_address_request, LIMINE_KERNEL_ADDRESS_REQUEST, 0);	 // Get the physical kernel address.
 LIMINE_REQUEST(kernel_file_request, LIMINE_KERNEL_FILE_REQUEST, 0);			 // For debug symbols.
-LIMINE_REQUEST(framebuffer_request, LIMINE_FRAMEBUFFER_REQUEST, 0);			 // Initial console frame buffer.
+LIMINE_REQUEST(framebuffer_request, LIMINE_FRAMEBUFFER_REQUEST, 1);			 // Initial console frame buffer.
 LIMINE_REQUEST(module_request, LIMINE_MODULE_REQUEST, 0);					 // Get all other modules, logo.
 #ifdef CONFIG_acpi
 LIMINE_REQUEST(rsdp_request, LIMINE_RSDP_REQUEST, 0);	 // Get ACPI RSDP table if enabled.
@@ -45,26 +45,6 @@ void kernel_boot()
 
 	BootInfo info = {0};
 
-	// Get early framebuffer.
-	kassert(framebuffer_request.response, "Unable to get a framebuffer!\n");
-	FrameBuffer buffer = {0};
-	const struct limine_framebuffer* buf = framebuffer_request.response->framebuffers[0];
-	// Construct a simple framebuffer. This will get overridden by a driver loaded at a later stage.
-	buffer.info.mmio_base = buf->address;
-	buffer.mode.width = buf->width;
-	buffer.mode.height = buf->height;
-	buffer.mode.bpp = buf->bpp;
-
-	// If no early framebuffer has been set previously, do it now.
-	if (fb_get_early() == NULL)
-	{
-		fb_set_early(&buffer);
-		terminal_init();
-	}
-
-	kmesg("Early framebuffer: Address = 0x%p, Resolution = %ux%ux%u\n", buffer.info.mmio_base, buffer.mode.width,
-		  buffer.mode.height, buffer.mode.bpp);
-
 	// Get the memory map.
 	kassert(memmap_request.response, "Unable to get memory map!\n");
 	struct limine_memmap_response* const res = memmap_request.response;
@@ -91,18 +71,68 @@ void kernel_boot()
 			default: map[i].usage = PhysMemoryUsage_Unknown; break;
 		}
 	}
+
 	// Make sure the first 4 GiB are identity mapped so we can write to "physical" memory.
 	kassert(hhdm_request.response, "Unable to get HHDM response!\n");
-	kmesg("HHDM offset: 0x%p\n", hhdm_request.response->offset);
 	kassert(kernel_address_request.response, "Unable to get kernel address info!\n");
-	kmesg("Kernel loaded at: 0x%p (0x%p)\n", kernel_address_request.response->virtual_base,
-		  kernel_address_request.response->physical_base);
 
 	// Initialize virtual memory using the memory map we got.
 	info.kernel_phys = (PhysAddr)kernel_address_request.response->physical_base;
 	info.kernel_virt = (void*)kernel_address_request.response->virtual_base;
 	info.phys_map = (void*)hhdm_request.response->offset;
 
+	// Initialize physical and virtual memory managers.
+	pm_init(info.phys_map, info.memory_map, info.mm_num);
+	vm_init(info.phys_map, info.kernel_phys, info.memory_map, info.mm_num);
+
+	// Get early framebuffer.
+	FrameBuffer buffer = {0};
+
+	if (framebuffer_request.response == NULL)
+		kmesg("Unable to get a framebuffer!\n");
+	else if (framebuffer_request.response->framebuffer_count > 0)
+	{
+		const struct limine_framebuffer* buf = framebuffer_request.response->framebuffers[0];
+		// Construct a simple framebuffer. This will get overridden by a driver loaded at a later stage.
+		buffer.info.mmio_base = buf->address;
+		buffer.mode.width = buf->width;
+		buffer.mode.height = buf->height;
+		buffer.mode.cpp = buf->bpp / 8;
+
+		buffer.funcs.copy_region = fb_default_copy_region;
+		buffer.funcs.fill_region = fb_default_fill_region;
+		buffer.funcs.draw_region = fb_default_draw_region;
+
+		// If no early framebuffer has been set previously, do it now.
+		if (fb_get_early() == NULL)
+		{
+			fb_set_early(&buffer);
+			terminal_init();
+		}
+
+		kmesg("Early framebuffer: Address = 0x%p, Resolution = %ux%ux%u\n", buffer.info.mmio_base, buffer.mode.width,
+			  buffer.mode.height, buffer.mode.cpp * 8);
+
+		// Print available video modes.
+		for (usize i = 0; i < buf->mode_count; i++)
+		{
+			const struct limine_video_mode* mode = buf->modes[i];
+			kmesg("    [%i] %ux%ux%u\n", i, mode->width, mode->height, mode->bpp);
+		}
+	}
+
+	// Print memory map.
+	kmesg("Physical memory map:\n");
+	for (usize i = 0; i < info.mm_num; i++)
+	{
+		kmesg("    [%u] 0x%p - 0x%p [%s]\n", i, info.memory_map[i].address,
+			  info.memory_map[i].address + info.memory_map[i].length,
+			  (info.memory_map[i].usage == PhysMemoryUsage_Free) ? "Usable" : "");
+	}
+	kmesg("HHDM offset: 0x%p\n", hhdm_request.response->offset);
+	kmesg("Kernel loaded at: 0x%p (0x%p)\n", kernel_address_request.response->virtual_base,
+		  kernel_address_request.response->physical_base);
+
 #ifdef CONFIG_acpi
 	// Get ACPI RSDP.
 	kassert(rsdp_request.response, "Unable to get ACPI RSDP!\n");
@@ -130,20 +160,24 @@ void kernel_boot()
 	info.cmd = kernel_res->kernel_file->cmdline;
 
 	// Get modules.
-	kassert(module_request.response, "Unable to get modules!\n");
-	kmesg("Got modules:\n");
-	const struct limine_module_response* module_res = module_request.response;
-	BootFile files[module_res->module_count];	 // TODO: Convert to kalloc'ed memory.
-	for (usize i = 0; i < module_res->module_count; i++)
+	if (module_request.response == NULL)
+		kmesg("Unable to get modules, or none were provided!\n");
+	else
 	{
-		files[i].address = module_res->modules[i]->address;
-		files[i].size = module_res->modules[i]->size;
-		files[i].path = module_res->modules[i]->path;
-		kmesg("    [%i] Address = 0x%p, Size = 0x%p, Path = \"%s\"\n", i, files[i].address, files[i].size,
-			  files[i].path);
+		kmesg("Got modules:\n");
+		const struct limine_module_response* module_res = module_request.response;
+		BootFile files[module_res->module_count];
+		for (usize i = 0; i < module_res->module_count; i++)
+		{
+			files[i].address = module_res->modules[i]->address;
+			files[i].size = module_res->modules[i]->size;
+			files[i].path = module_res->modules[i]->path;
+			kmesg("    [%i] Address = 0x%p, Size = 0x%p, Path = \"%s\"\n", i, files[i].address, files[i].size,
+				  files[i].path);
+		}
+		info.file_num = module_res->module_count;
+		info.files = files;
 	}
-	info.file_num = module_res->module_count;
-	info.files = files;
 
 	arch_init(&info);
 	kernel_main(&info);