aboutsummaryrefslogtreecommitdiff
path: root/arch/riscv/init
diff options
context:
space:
mode:
authorKimplul <kimi.h.kuparinen@gmail.com>2021-12-19 17:10:36 +0200
committerKimplul <kimi.h.kuparinen@gmail.com>2021-12-19 17:10:36 +0200
commit9966b49db468de0168c7a455dfb5b4c66c413c4d (patch)
treedf31febe5e1ae52bae68ebe1df8b4469b97e0546 /arch/riscv/init
parent8bb1e280280c2f30740defca68ea643c56a3d880 (diff)
downloadkmi-9966b49db468de0168c7a455dfb5b4c66c413c4d.tar.gz
kmi-9966b49db468de0168c7a455dfb5b4c66c413c4d.zip
Massive changes to jump to userspace
Diffstat (limited to 'arch/riscv/init')
-rw-r--r--arch/riscv/init/head.S7
-rw-r--r--arch/riscv/init/init.c337
2 files changed, 0 insertions, 344 deletions
diff --git a/arch/riscv/init/head.S b/arch/riscv/init/head.S
deleted file mode 100644
index 3589ead..0000000
--- a/arch/riscv/init/head.S
+++ /dev/null
@@ -1,7 +0,0 @@
-.section .init.start
-.global _start
-.type _start, @function
-_start:
- li sp, PM_STACK_TOP
- /* go to proper init */
- j init
diff --git a/arch/riscv/init/init.c b/arch/riscv/init/init.c
deleted file mode 100644
index 721712c..0000000
--- a/arch/riscv/init/init.c
+++ /dev/null
@@ -1,337 +0,0 @@
-/* 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 <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;
-};
-
-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;
- };
-
- 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()
-{
- extern char __init_end, __kernel_size;
- pm_t dst = alloc_page(MM_MPAGE, 0);
- memmove((void *)dst, &__init_end, (size_t)&__kernel_size);
-
- 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;
-}
-
-static vm_t prepare_tmp_pte(struct vm_branch_t *branch)
-{
- /* make sure the TMP_PTE is mapped to *something* */
- map_vmem(branch, 0, TMP_PTE, VM_R | VM_W | VM_V, MM_KPAGE);
-
- struct vm_branch_t *tmp_pte = arch_get_tmp_pte(branch);
-
- vm_t addr = TMP_PTE + MM_KPAGE_SIZE;
- map_vmem(branch, (vm_t)tmp_pte, addr, VM_R | VM_W | VM_V, MM_KPAGE);
- return addr;
-}
-
-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,
- vm_t v)
-{
- 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.tmp_pte = v;
-
- 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;
-}
-
-void init(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();
- vm_t v = prepare_tmp_pte(b);
- struct init_data_t d = populate_initdata(fdt, o, p, b, v);
- 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);
-}