Start of a platform-independent paging interface.

2 files changed, 40 insertions, 5 deletions

diff --git a/boards/qemu-virt/qemu-virt.ld b/boards/qemu-virt/qemu-virt.ld
index 1fd3c22..41b4b40 100644
--- a/boards/qemu-virt/qemu-virt.ld
+++ b/boards/qemu-virt/qemu-virt.ld
@@ -10,12 +10,14 @@ SECTIONS {
 		*(.text .text.*)
 	}
 	. = ALIGN(0x1000);
+	PROVIDE(kernel_rx_end = .);
 	.rodata : {
 		*(.srodata .srodata.*)
 		. = ALIGN(16);
 		*(.rodata .rodata.*)
 	}
 	. = ALIGN(0x1000);
+	PROVIDE(kernel_ro_end = .);
 	.data : {
 		*(.sdata .sdata.*)
 		. = ALIGN(16);
@@ -28,6 +30,13 @@ SECTIONS {
 		*(.bss .bss.*)
 	}
 	. = ALIGN(0x1000);
+	PROVIDE(kernel_rw_end = .);
+	.trampoline_page : {
+		PROVIDE(trampoline_start = .);
+		*(.trampoline_page)
+		. = trampoline_start + 0x1000;
+	}
+	. = ALIGN(0x1000);
 	.hart0_initial_stack : {
 		PROVIDE(hart0_initial_stack = .);
 		. += 0x1000;
diff --git a/boards/qemu-virt/qemu-virt.s b/boards/qemu-virt/qemu-virt.s
index f0599da..36ccee0 100644
--- a/boards/qemu-virt/qemu-virt.s
+++ b/boards/qemu-virt/qemu-virt.s
@@ -71,17 +71,36 @@ _start:
 
 .type hart0_full_boot, STT_FUNC
 hart0_full_boot:
-	## Set up hart0's stack.
-	la sp, hart0_initial_stack_top
+	## Set up hart0's stack, leaving room for the EarlyBootAddrs.
+	la sp, hart0_initial_stack_top - 9 * 8
 
-	## Write a canary to hart0's stack.
+	## Write a canary to the bottom of hart0's stack.
 	li t0, 0xdead0bad0defaced
 	la t1, hart0_initial_stack
 	sd t0, (t1)
 
+	## Store the DeviceTree and the appropriate addresses into the
+	## EarlyBootAddrs.
+	sd a1, (0 * 8)(sp)
+	la t0, kernel_start
+	sd t0, (1 * 8)(sp)
+	la t0, kernel_end
+	sd t0, (2 * 8)(sp)
+	la t0, kernel_rx_end
+	sd t0, (3 * 8)(sp)
+	la t0, kernel_ro_end
+	sd t0, (4 * 8)(sp)
+	la t0, kernel_rw_end
+	sd t0, (5 * 8)(sp)
+	sd t1, (6 * 8)(sp) # This is still hart0_initial_stack from above.
+	la t0, hart0_initial_stack_top
+	sd t0, (7 * 8)(sp)
+	la t0, trampoline_start
+	sd t0, (8 * 8)(sp)
+
 	## Call hart0_early_boot, passing it the DeviceTree we received and
 	## getting back the address of a stack to switch to.
-	mv a0, a1
+	mv a0, sp
 	call hart0_early_boot
 
 	## Switch to the returned stack.
@@ -99,7 +118,14 @@ hart0_full_boot:
 
 .type wait_for_hart0, STT_FUNC
 wait_for_hart0:
-	# TODO
+	## TODO
 	wfi
 	j wait_for_hart0
 .size wait_for_hart0, . - wait_for_hart0
+
+.section .trampoline_page
+
+trap_handler:
+	## TODO
+	wfi
+	j trap_handler