memory detection

9 files changed, 113 insertions, 17 deletions

diff --git a/sys/dev/dev_init.c b/sys/dev/dev_init.c
index fc70853..9933c2a 100644
--- a/sys/dev/dev_init.c
+++ b/sys/dev/dev_init.c
@@ -5,18 +5,46 @@
 #include <string.h>
 #include <stdint.h>
 
-void
-dev_init(struct fdt_header *fdt)
+
+static void
+mem_init(struct fdt_header *fdt, struct devicetree *dt)
 {
+
+	int memory = fdt_path_offset(fdt, "/memory");
+	if (memory < 0)
+		printf("[dev_init] failed to find memory node\n");
+
+	int len;
+
+	struct _reg *val = fdt_getprop(fdt, memory, "reg", &len);
+	/* bad idea */
+	dt->memory.origin = fdt64_to_cpu(val->address);
+	dt->memory.size = fdt64_to_cpu(val->size);
+	printf("[mem_init] found %dMB of memory at %p\n", dt->memory.size >> 20, dt->memory.origin);
+
+	int n = fdt_num_mem_rsv(fdt);
+	printf("[mem_init] found %d memory reserve map entries\n", n);
+}
+
+
+struct devicetree
+dev_init(struct fdt_header *fdt) 
+{
+	struct devicetree dt = {0};
+
 	if (fdt_check_header(fdt) == 0) 
 		printf("[dev_init] valid fdt at %p\n", fdt);
 	else
 		printf("[dev_init] error: fdt_check_header()\n");
 
-	int offset = fdt_next_node(fdt, offset, 0);
-	do {
-		printf("[dev_init] found %s\n", fdt_get_name(fdt, offset, NULL));
-		offset = fdt_next_node(fdt, offset, 0);
-	} while (offset != -FDT_ERR_NOTFOUND);
+	printf("[dev_init] detecting memory...\n");
+	mem_init(fdt, &dt);
+
+//	int offset = fdt_next_node(fdt, offset, 0);
+//	do {
+//		printf("[dev_init] found %s\n", fdt_get_name(fdt, offset, 0));
+//		offset = fdt_next_node(fdt, offset, 0);
+//	} while (offset != -FDT_ERR_NOTFOUND);
+	return dt;
 }
 
diff --git a/sys/include/asm.h b/sys/include/asm.h
index 0995f88..d345712 100644
--- a/sys/include/asm.h
+++ b/sys/include/asm.h
@@ -53,4 +53,10 @@ read_tp(void)
 	return x;
 }
 
+static inline void 
+csrw_satp(uint64_t x)
+{
+	asm volatile("csrw satp, %0" : : "r"(x));
+}
+
 #endif /* _ASM_H */ 
diff --git a/sys/include/dev.h b/sys/include/dev.h
index b8bfef8..657c04c 100644
--- a/sys/include/dev.h
+++ b/sys/include/dev.h
@@ -2,7 +2,37 @@
 #define _DEV_H
 
 #include <libfdt.h>
+#include <stdint.h> 
 
-void dev_init(struct fdt_header* fdt);
+enum { DT_MMUTYPE_SV32, DT_MMUTYPE_SV39, DT_MMUTYPE_SV48 };
+
+struct _reg {
+	fdt64_t address;
+	fdt64_t size;
+};
+/* unflattend device tree */ 
+struct devicetree {
+	const char *compat;
+	const char *model;
+	int nproc;
+	/* main cpu, monitor/alternative cores will be ignored for now */
+	struct {
+		short mmu_type;
+		const char *isa;
+		unsigned int freq;
+	} cpu;
+	struct {
+		uintptr_t origin;
+	 	uintptr_t size;
+	} memory;
+	struct {
+		unsigned int freq;
+		const char *compat;
+		int interrupt;
+		struct _reg reg;
+	} uart;
+};
+
+struct devicetree dev_init(struct fdt_header* fdt);
 
 #endif /* _DEV_H */
diff --git a/sys/include/kalloc.h b/sys/include/kalloc.h
index 10adbda..5553d94 100644
--- a/sys/include/kalloc.h
+++ b/sys/include/kalloc.h
@@ -7,7 +7,7 @@ void *kzalloc(void);
 
 void kfree(void *);
 
-void kalloc_init(void);
+void kalloc_init(size_t);
 
 void walkfree(void);
 
diff --git a/sys/include/sbi.h b/sys/include/sbi.h
index 94c3749..86ca295 100644
--- a/sys/include/sbi.h
+++ b/sys/include/sbi.h
@@ -1,6 +1,8 @@
 #ifndef _SBI_H
 #define _SBI_H
 
+#include <stdint.h> 
+
 struct sbiret {
 	long err;
 	long val;
@@ -58,6 +60,12 @@ sbi_console_putchar(int c)
 	sbi_ecall(1, 0, c, 0, 0, 0, 0, 0);
 }
 
+static inline void 
+sbi_debug_console_write_byte(uint8_t byte)
+{
+	sbi_ecall(0x4442434E, 0x2, 'c', 0, 0, 0, 0, 0);
+}
+
 static inline void
 sbi_shutdown(void)
 {
diff --git a/sys/include/vm.h b/sys/include/vm.h
new file mode 100644
index 0000000..1883ea7
--- /dev/null
+++ b/sys/include/vm.h
@@ -0,0 +1,6 @@
+#ifndef _VM_H
+#define _VM_H
+
+void vminit(void);
+
+#endif /* _VM_H */
diff --git a/sys/sys/init.c b/sys/sys/init.c
index 48aeb97..05e8d49 100644
--- a/sys/sys/init.c
+++ b/sys/sys/init.c
@@ -20,12 +20,16 @@ init(unsigned long hartid, struct fdt_header *fdt)
 
 	printf("booting from hart #%d\n", hartid);
 
-	printf("setting up the heap at %p\n", HEAP_START);
-	kalloc_init();
 	printf_init();
 	printf("done!\n");
 
-	dev_init(fdt);
+	struct devicetree dt = dev_init(fdt);
+
+	printf("setting up page frame allocator at %p\n", HEAP_START);
+	kalloc_init(dt.memory.origin + dt.memory.size);
+	printf("done!\n");
+
+//	walkfree();
 
 	printf("bringing up other harts...\n");
 	for (int i = 0; i < NPROC; ++i) {
diff --git a/sys/sys/mm/kalloc.c b/sys/sys/mm/kalloc.c
index 6cf888a..db2bea8 100644
--- a/sys/sys/mm/kalloc.c
+++ b/sys/sys/mm/kalloc.c
@@ -6,13 +6,15 @@
 #include <kalloc.h>
 #include <stdio.h>
 
+#define ALIGNPG(n)	(((n) + (uintptr_t)PAGE_SIZE - 1) & ~((uintptr_t)PAGE_SIZE))
+
 extern uint64_t HEAP_START; 
 
 typedef struct freenode {
 	struct freenode *next;
 } freenode_t;
 
-freenode_t *head = NULL;
+freenode_t *head = {0};
 static spinlock_t mutex;
 
 void *
@@ -40,8 +42,9 @@ kzalloc(void)
 void
 kfree(void *p)
 {
-	if (p == NULL || (uint64_t)p % (uint64_t)PAGE_SIZE)
+	if (p == NULL) {
 		return;
+	}
 
 	acquire(&mutex);
 	freenode_t *tmp = head;
@@ -51,11 +54,12 @@ kfree(void *p)
 }
 
 void
-kalloc_init(void)
+kalloc_init(uintptr_t end)
 {
 	initlock(&mutex);
 	freenode_t *p = (freenode_t*)HEAP_START;
-	for (;(unsigned long)p + PAGE_SIZE <= (HEAP_START + 0x100000); p += PAGE_SIZE) {
+	end = ALIGNPG(end);
+	for (;(unsigned long)p + PAGE_SIZE <= end; p += PAGE_SIZE) {
 		kfree(p);
 	}
 }
@@ -65,7 +69,7 @@ walkfree(void)
 {
 	freenode_t *node = head;
 	int nfree = 0;
-	while (node) {
+	while (node != NULL) {
 		printf("freenode at %p\n", node);
 		node = node->next;
 		nfree++;
diff --git a/sys/sys/vm/vm.c b/sys/sys/vm/vm.c
new file mode 100644
index 0000000..a9173be
--- /dev/null
+++ b/sys/sys/vm/vm.c
@@ -0,0 +1,10 @@
+#include <vm.h>
+#include <asm.h>
+
+#define SV39 (8L << 60)
+
+void
+vminit(void)
+{
+	csrw_satp(SATP, (uint64_t)pt >> 12);
+}