More sensible init

+ Who knew some reservations were a good thing? (at least relativelyy
  speaking)

6 files changed, 49 insertions, 14 deletions

diff --git a/arch/riscv/conf/apos.its b/arch/riscv/conf/apos.its
index 15db4a4..da48860 100644
--- a/arch/riscv/conf/apos.its
+++ b/arch/riscv/conf/apos.its
@@ -12,8 +12,8 @@
 			arch = "riscv";
 			os = "apos";
 			compression = "none";
-			load = <0x83800000>;
-			entry = <0x83800000>;
+			load = <0x80080000>;
+			entry = <0x80080000>;
 			hash-1 {
 				algo = "sha1";
 			};
diff --git a/arch/riscv/conf/init-link.S b/arch/riscv/conf/init-link.S
index 642e831..53d24ab 100644
--- a/arch/riscv/conf/init-link.S
+++ b/arch/riscv/conf/init-link.S
@@ -1,5 +1,5 @@
 OUTPUT_ARCH(riscv)
-ENTRY(main)
+ENTRY(init)
 
 SECTIONS {
 	. = ABSOLUTE(PM_KERN);
@@ -27,4 +27,5 @@ SECTIONS {
 	}
 
 	__init_end = . ;
+	__kernel_size = <KERNEL_SIZE>;
 }
diff --git a/arch/riscv/config.h b/arch/riscv/config.h
index fa3c178..35e0b6e 100644
--- a/arch/riscv/config.h
+++ b/arch/riscv/config.h
@@ -2,14 +2,16 @@
 
 /* --- START ARCH USER CONFIG VALUES --- */
 /* physical address to which the kernel will be loaded */
-#define PM_KERN		0x83800000
+#define RAM_BASE	0x80000000
+#define PM_KERN		(RAM_BASE + SZ_512K)
 /* --- END ARCH USER CONFIG VALUES --- */
 
 /* don't touch >:( */
 
 #define PM_STACK_BASE	(PM_KERN + SZ_2M)
 #define PM_STACK_TOP	(PM_STACK_BASE + SZ_2M - 2)
-#define VM_KERN		(-SZ_1G)
+#define VM_DMAP		(-SZ_256G) /* testing for now */
+#define VM_KERN		(VM_DMAP + SZ_256K)
 #define TMP_PTE		(-SZ_2G)
 #define ROOT_PTE	(0)
 #define ROOT_REGION	(SZ_4K)
diff --git a/arch/riscv/init/init.c b/arch/riscv/init/init.c
index d9b32a0..728f8dd 100644
--- a/arch/riscv/init/init.c
+++ b/arch/riscv/init/init.c
@@ -1,5 +1,6 @@
 #include <apos/types.h>
 #include <apos/attrs.h>
+#include <apos/utils.h>
 #include <vmem.h>
 #include <csr.h>
 
@@ -8,22 +9,47 @@ struct __packed init_vmem {
 	int *leaf[512];
 };
 
-struct init_vmem root_branch;
+struct init_vmem *root_branch;
 
-/* assume Sv48 for now */
-void init_lowmem()
+/* assume Sv39 for now */
+void init_vmem()
 {
 	size_t flags = VM_V | VM_X | VM_R | VM_W;
+
+	extern char *__init_start;
+	root_branch = (struct init_vmem *)align_down((size_t)&__init_start - SZ_4K, SZ_4K);
 	for(size_t i = 0; i < 512; ++i)
-		root_branch.leaf[i] = (int *)((1UL << 37) * i | flags);
+		root_branch->leaf[i] = 0;
+
+	/* direct mapping (temp) */
+	for(size_t i = 0; i < 256; ++i)
+		root_branch->leaf[i] = (int *)((1UL << 28) * i | flags);
+
+	/* kernel (also sort of direct mapping) */
+	/* FIXME set up actually correct addressing retard */
+	for(size_t i = 256; i < 512; ++i)
+	root_branch->leaf[256] = (int *)(((RAM_BASE >> 12) << 10) | flags);
+
+	csr_write(CSR_SATP, SATP_MODE_Sv39 | ((size_t)root_branch >> 12));
+}
+
+void move_kernel()
+{
+	extern char *__init_end;
+	extern char *__kernel_size;
 
-	 csr_write(CSR_SATP, SATP_MODE_Sv48 | ((size_t)&root_branch >> 12));
+	size_t sz = (size_t)&__kernel_size;
+	char *src = (char *)&__init_end;
+	char *dst = (char *)VM_KERN;
+	for(size_t i = 0; i < sz; ++i)
+		dst[i] = src[i];
 }
 
-void __section(".init.start") main(void *fdt)
+void __init init(void *fdt)
 {
 	extern char *__init_end;
-	void (*kernel_main)(void *fdt) = (void (*)(void *))(VM_KERN + (size_t)&__init_end);
-	init_lowmem();
+	void (*kernel_main)(void *fdt) = (void (*)(void *))(VM_KERN);
+	init_vmem();
+	move_kernel();
 	kernel_main(fdt);
 }
diff --git a/arch/riscv/kernel/main.c b/arch/riscv/kernel/main.c
index 6c504f8..5576d68 100644
--- a/arch/riscv/kernel/main.c
+++ b/arch/riscv/kernel/main.c
@@ -54,7 +54,7 @@ static struct pm_layout_t get_memlayout(void *fdt)
 
 	/* -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};
+	return (struct pm_layout_t){__va(base), __va(top)};
 }
 
 static pm_t get_kerneltop()
@@ -276,6 +276,8 @@ static void init_proc(void *fdt, struct vm_branch_t *b)
 
 void __main main(void *fdt)
 {
+	/* correct fdt pointer */
+	fdt = (void *)__va(fdt);
 	init_dbg(fdt);
 	dbg_fdt(fdt);
 
diff --git a/arch/riscv/mm.txt b/arch/riscv/mm.txt
index fa06180..30ffc88 100644
--- a/arch/riscv/mm.txt
+++ b/arch/riscv/mm.txt
@@ -14,6 +14,10 @@ Offset		| Size		| Purpose
 -255 GiB	| 1 GiB		| Kernel IO
 -256 GiB	| 1 GiB		| Kernel
 
+(alternate scheme: Kernel vmem is itself a direct mapping?)
+(first 256KiB page reserved for whatever, next 256KiB reserved for kernel vma,
+ next 512KiB reserved for kernel pma?)
+
 Sv48:
 
 Offset		| Size		| Purpose