Revert "still some issues with vmem"

This reverts commit 69d13626a37e33f31627a1144605a8fb93684d25.

4 files changed, 18 insertions, 314 deletions

diff --git a/arch/riscv/conf/init-link.S b/arch/riscv/conf/init-link.S
index 752edc2..642e831 100644
--- a/arch/riscv/conf/init-link.S
+++ b/arch/riscv/conf/init-link.S
@@ -27,5 +27,4 @@ SECTIONS {
 	}
 
 	__init_end = . ;
-	__kernel_size = <KERNEL_SIZE>;
 }
diff --git a/arch/riscv/init/init.c b/arch/riscv/init/init.c
index 7606feb..d9b32a0 100644
--- a/arch/riscv/init/init.c
+++ b/arch/riscv/init/init.c
@@ -1,322 +1,29 @@
-/* TODO: cleanup :P */
-
-#include <apos/init.h>
-#include <apos/sizes.h>
 #include <apos/types.h>
-#include <apos/string.h>
-#include <apos/debug.h>
-#include <apos/pmem.h>
-#include <apos/vmem.h>
-#include <apos/utils.h>
-#include <libfdt.h>
-#include <pages.h>
+#include <apos/attrs.h>
+#include <vmem.h>
 #include <csr.h>
 
-struct pm_layout_t {
-	pm_t base;
-	pm_t top;
-};
-
-struct pm_orders_t {
-	size_t max_order;
-	size_t bits[10];
-	size_t page_shift;
+/* assume 64 bit for now */
+struct __packed init_vmem {
+	int *leaf[512];
 };
 
-static struct pm_layout_t get_memlayout(void *fdt)
-{
-	struct cell_info_t ci = get_reginfo(fdt, "/memory");
-	int mem_offset = fdt_path_offset(fdt, "/memory");
-	uint8_t *mem_reg =
-		(uint8_t *) fdt_getprop(fdt, mem_offset, "reg", NULL);
-
-	/* if riscv128 comes around we will probably see addr_cells == 4, but
-	 * I'm not too concerned about it at the moment */
-	pm_t base = (pm_t)fdt_load_int_ptr(ci.addr_cells, mem_reg);
-
-	if(ci.addr_cells == 2)
-		mem_reg += sizeof(fdt64_t);
-	else
-		mem_reg += sizeof(fdt32_t);
-
-	/* -1 because base is a legitimate memory address */
-	pm_t top = (pm_t)fdt_load_int_ptr(ci.size_cells, mem_reg) + base - 1;
-	return (struct pm_layout_t){base, top};
-}
-
-#ifdef DEBUG
-
-static void init_debug(void *fdt)
-{
-	struct dbg_info_t dbg = dbg_from_fdt(fdt);
-	dbg_init(dbg.dbg_ptr, dbg.dev);
-}
-
-#else
-#define init_debug(...)
-#endif
-
-static pm_t get_kerneltop()
-{
-	/* interesting, for some reason if I define these to be just char
-	 * pointers I get some wacky values. Not sure why that would be, but
-	 * this works. */
-	extern char __init_end, __kernel_size;
-	return (pm_t)&__init_end + (pm_t)&__kernel_size;
-}
-
-static pm_t get_initrdtop(void *fdt)
-{
-	int chosen_offset = fdt_path_offset(fdt, "/chosen");
-	struct cell_info_t ci = get_cellinfo(fdt, chosen_offset);
-
-	void *initrd_end_ptr = (void *)fdt_getprop(fdt, chosen_offset,
-			"linux,initrd-end", NULL);
-
-	return (pm_t)fdt_load_int_ptr(ci.addr_cells, initrd_end_ptr);
-}
-
-static pm_t get_initrdbase(void *fdt)
-{
-	int chosen_offset = fdt_path_offset(fdt, "/chosen");
-	struct cell_info_t ci = get_cellinfo(fdt, chosen_offset);
-
-	void *initrd_base_ptr = (void *)fdt_getprop(fdt, chosen_offset,
-			"linux,initrd-start", NULL);
-
-	return (pm_t)fdt_load_int_ptr(ci.addr_cells, initrd_base_ptr);
-}
-
-static pm_t get_fdttop(void *fdt)
-{
-	const char *b = (const char *)fdt;
-	return (pm_t)(b + fdt_totalsize(fdt));
-}
-
-static pm_t get_fdtbase(void *fdt)
-{
-	/* lol */
-	return (pm_t)fdt;
-}
-
-static void mark_area_used(pm_t base, pm_t top)
-{
-	size_t area_left = top - base;
-	/* TODO: add in a method to make sure that we use as large mappings as
-	 * possible. */
-	while(area_left >= MM_KPAGE_SIZE){
-		mark_used(base, MM_KPAGE);
-		area_left -= MM_KPAGE_SIZE;
-		base += MM_KPAGE_SIZE;
-	}
-
-	if(area_left != 0)
-		mark_used(base, MM_KPAGE_SIZE);
-}
-
-static void mark_reserved_mem(void *fdt)
-{
-	int rmem_offset = fdt_path_offset(fdt, "/reserved-memory/mmode_resv0");
-	struct cell_info_t ci = get_reginfo(fdt, "/reserved-memory/mmode_resv0");
-	uint8_t *rmem_reg = (uint8_t *)fdt_getprop(fdt, rmem_offset, "reg", NULL);
-
-	pm_t base = (pm_t)fdt_load_int_ptr(ci.addr_cells, rmem_reg);
-
-	if(ci.addr_cells == 2)
-		rmem_reg += sizeof(fdt64_t);
-	else
-		rmem_reg += sizeof(fdt32_t);
-
-	pm_t top = (pm_t)fdt_load_int_ptr(ci.size_cells, rmem_reg) + base - 1;
-	mark_area_used(base, top);
-}
-
-static struct pm_orders_t init_pmem(void *fdt)
-{
-	enum mm_mode_t mmode = get_mmode(fdt);
-
-	size_t max_order = 0;
-	size_t order_bits = 9;
-	switch(mmode){
-		case Sv32:
-			max_order = 1;
-			order_bits = 10;
-			break;
-
-		case Sv39:
-			max_order = 2;
-			break;
-
-		case Sv48:
-			max_order = 3;
-			break;
-	};
+struct init_vmem root_branch;
 
-	size_t bits[10] = {0};
-	for(size_t i = 0; i <= max_order; ++i)
-		bits[i] = order_bits;
-
-	init_mem(max_order, bits, 12);
-
-	struct pm_orders_t ret = {max_order, {0}, 12};
-	for(size_t i = 0; i <= __mm_max_order; ++i)
-		ret.bits[i] = bits[i];
-
-	return ret;
-}
-
-static struct pm_layout_t setup_pmem(void *fdt)
-{
-	struct pm_layout_t pmem = get_memlayout(fdt);
-
-	pm_t initrd_top = get_initrdtop(fdt);
-	pm_t kernel_top = get_kerneltop();
-	pm_t fdt_top = get_fdttop(fdt);
-
-	pm_t top = MAX3(kernel_top, initrd_top, fdt_top);
-	dbg("initrd_top:\t%#lx\n", initrd_top);
-	dbg("kernel_top:\t%#lx\n", kernel_top);
-	dbg("fdt_top:\t%#lx\n", fdt_top);
-
-	/* TODO: check that pmap placement doesn't overwrite anything, such as
-	 * stack or go over top address of memory */
-	size_t probe_size = probe_pmap(pmem.base, pmem.top - pmem.base);
-	/* riscv handles two byte boundaries better than one byte, so align
-	 * upwards */
-	pm_t pmap_base = align_up(top + 1, 2);
-	size_t actual_size = populate_pmap(pmem.base, pmem.top - pmem.base,
-			pmap_base);
-
-	/* TODO: not entirely sure what to do about this, probably give up trying to
-	 * boot? */
-	if(probe_size != actual_size){
-		dbg("BUG! probe_size (%#lx) != actual_size (%#lx)\n",
-				probe_size, actual_size);
-	}
-
-	/* mark init stack, at the moment always mapped to 2M */
-	mark_used(PM_STACK_BASE, MM_MPAGE);
-
-	/* mark kernel, at the moment it is always mapped to a 2M partition */
-	mark_used(PM_KERN, MM_MPAGE);
-
-	/* mark fdt and initrd */
-	mark_area_used(get_initrdbase(fdt), initrd_top);
-	mark_area_used(get_fdtbase(fdt), fdt_top);
-
-	/* mark pmap */
-	mark_area_used(pmap_base, pmap_base + actual_size);
-
-	/* mark reserved mem */
-	mark_reserved_mem(fdt);
-
-	return (struct pm_layout_t){.base = pmap_base, .top = actual_size + pmap_base};
-}
-
-pm_t move_kernel()
+/* assume Sv48 for now */
+void init_lowmem()
 {
-	extern char __init_end, __kernel_size;
-	pm_t dst = alloc_page(MM_MPAGE, 0);
-	memmove((void *)dst, &__init_end, (size_t)&__kernel_size);
+	size_t flags = VM_V | VM_X | VM_R | VM_W;
+	for(size_t i = 0; i < 512; ++i)
+		root_branch.leaf[i] = (int *)((1UL << 37) * i | flags);
 
-	return dst;
-}
-
-struct vm_branch_t *prepare_vmem()
-{
-	pm_t kernel_dst = move_kernel();
-
-	/* TODO: check if this actually works */
-	struct vm_branch_t *branch = (struct vm_branch_t *)alloc_page(MM_KPAGE, 0);
-	memset(branch, 0, sizeof(struct vm_branch_t));
-
-	/* TODO: check mapping flags, also iron out possible bugs etc in
-	 * map_vmem */
-	/* map kernel */
-	map_vmem(branch, kernel_dst, VM_KERN, VM_R | VM_W | VM_G | VM_X | VM_V, MM_MPAGE);
-
-	/* map init */
-	map_vmem(branch, PM_KERN, PM_KERN, VM_R | VM_W | VM_X | VM_V, MM_MPAGE);
-
-	/* map stack */
-	map_vmem(branch, PM_STACK_BASE, PM_STACK_BASE, VM_R | VM_W | VM_V, MM_MPAGE);
-
-	/* map root pte */
-	map_vmem(branch, (pm_t)branch, ROOT_PTE, VM_R | VM_W | VM_V, MM_KPAGE);
-
-	/* TODO: map more stuff? */
-	return branch;
-}
-
-void start_vmem(void *fdt, struct vm_branch_t *branch)
-{
-	/* TODO: get ASID from CPU id */
-
-	/* TODO: probably unnecessary optimisations but this could be cached? */
-	enum mm_mode_t m = get_mmode(fdt);
-
-	if(m == Sv32)
-		csr_write(CSR_SATP, SATP_MODE_Sv32 | pm_to_pnum((pm_t)(branch)));
-	else if (m == Sv39)
-		csr_write(CSR_SATP, SATP_MODE_Sv39 | pm_to_pnum((pm_t)(branch)));
-	else
-		csr_write(CSR_SATP, SATP_MODE_Sv48 | pm_to_pnum((pm_t)(branch)));
-
-	__asm__ ("sfence.vma" : : : "memory");
-	/* Sv57 && Sv64 in the future? */
-}
-
-struct init_data_t populate_initdata(void *fdt, struct pm_orders_t o,
-		struct pm_layout_t p,
-		struct vm_branch_t *b)
-{
-	extern char __init_start, __init_end;
-
-	struct init_data_t d = {0};
-	d.init_base = (pm_t)&__init_start;
-	d.init_top = (pm_t)&__init_end;
-
-	d.initrd_base = get_initrdbase(fdt);
-	d.initrd_top = get_initrdtop(fdt);
-
-	d.pmap_base = p.base;
-	d.pmap_top = p.top;
-
-	d.fdt_base = get_fdtbase(fdt);
-	d.fdt_top = get_fdttop(fdt);
-
-	d.stack_base = PM_STACK_BASE;
-	d.stack_top = PM_STACK_TOP;
-
-	d.kernel_vm_base = b;
-
-	d.max_order = o.max_order;
-	for(size_t i = 0; i <= __mm_max_order; ++i)
-		d.bits[i] = o.bits[i];
-	d.page_shift = o.page_shift;
-
-	/* initialize pmap in vmem */
-	pm_t addr = p.base;
-	while(addr < p.top){
-		map_vmem(b, addr, addr, VM_R | VM_W | VM_V, MM_MPAGE);
-		addr += MM_MPAGE_SIZE;
-	}
-
-	return d;
+	 csr_write(CSR_SATP, SATP_MODE_Sv48 | ((size_t)&root_branch >> 12));
 }
 
 void __section(".init.start") main(void *fdt)
 {
-	init_debug(fdt);
-	dbg_fdt(fdt);
-
-	struct pm_orders_t o = init_pmem(fdt);
-	struct pm_layout_t p = setup_pmem(fdt);
-	struct vm_branch_t *b = prepare_vmem();
-	struct init_data_t d = populate_initdata(fdt, o, p, b);
-	start_vmem(fdt, b);
-
-	/* update_pmap(TODO: figure out where to place pmap in vmem); */
-	void (*main)(struct init_data_t) = (void (*)(struct init_data_t))VM_KERN;
-	main(d);
+	extern char *__init_end;
+	void (*kernel_main)(void *fdt) = (void (*)(void *))(VM_KERN + (size_t)&__init_end);
+	init_lowmem();
+	kernel_main(fdt);
 }
diff --git a/arch/riscv/common/vmem.c b/arch/riscv/kernel/vmem.c
index 4cb84a6..4cb84a6 100644
--- a/arch/riscv/common/vmem.c
+++ b/arch/riscv/kernel/vmem.c
diff --git a/arch/riscv/source.mk b/arch/riscv/source.mk
index ef61611..0e9a5c3 100644
--- a/arch/riscv/source.mk
+++ b/arch/riscv/source.mk
@@ -1,8 +1,6 @@
-COMMON_LOCAL	!= echo arch/riscv/common/*.[cS]
 KERNEL_LOCAL	!= echo arch/riscv/kernel/*.[cS]
-KERNEL_SOURCES	+= $(KERNEL_LOCAL) $(COMMON_LOCAL)
-INIT_LOCAL	!= echo arch/riscv/init/*.[cS]
-INIT_SOURCES	+= $(INIT_LOCAL) $(COMMON_LOCAL)
+KERNEL_SOURCES	+= $(KERNEL_LOCAL)
+INIT_SOURCES	+= arch/riscv/init/init.c
 
 CLEANUP_CMD	:= ./arch/riscv/conf/rmimage.sh