X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Farmv7%2Fstart.S;h=3c0779fb8ce4afc73bbf5c8f7619850451617cb3;hb=1389dd6a77cfe0f01ae941f6f696bd5eda22e959;hp=e1bbe0c97765f4c4824cfd9391f99f02c3bbf10f;hpb=f9c581641afeb556188e84428febd4011e61edc2;p=tpg%2Facess2.git

diff --git a/Kernel/arch/armv7/start.S b/Kernel/arch/armv7/start.S
index e1bbe0c9..3c0779fb 100644
--- a/Kernel/arch/armv7/start.S
+++ b/Kernel/arch/armv7/start.S
@@ -1,19 +1,20 @@
-KERNEL_BASE =	0x80000000
-PCI_PADDR   =	0x60000000	@ Realview
-UART0_PADDR =	0x10009000	@ Realview
+
+#include "include/assembly.h"
+#include "include/options.h"
+
 @
 @ Exception defs taken from ARM DDI 0406B
 @ 
 .section .init
 interrupt_vector_table:
-	b _start @ Reset
-	b .	@ #UD
-	b SyscallHandler @ SVC (SWI assume)
-	b .	@ Prefetch abort
-	b .	@ Data abort
-	b .	@ Not Used
-	b IRQHandler	@ IRQ
-	b .	@ FIQ (Fast interrupt)
+ivt_reset:	b _start	@ 0x00 Reset
+ivt_undef:	b .     	@ 0x04 #UD
+ivt_svc:	b SVC_Handler	@ 0x08 SVC (used to be called SWI)
+ivt_prefetch:	b PrefetchAbort	@ 0x0C Prefetch abort
+ivt_data:	b DataAbort	@ 0x10 Data abort
+ivt_unused:	b .     	@ 0x14 Not Used
+ivt_irq:	b IRQHandler	@ 0x18 IRQ
+ivt_fiq:	b .     	@ 0x1C FIQ (Fast interrupt)
 
 .globl _start
 _start:
@@ -27,63 +28,200 @@ _start:
 	mov r0, #3
 	mcr p15, 0, r0, c3, c0, 0	@ Set Domain 0 to Manager
 
+	@ Enable VMSA
 	mrc p15, 0, r0, c1, c0, 0
 	orr r0, r0, #1
 	orr r0, r0, #1 << 23
 	mcr p15, 0, r0, c1, c0, 0
 
-	ldr sp, =stack+0x10000	@ Set up stack
+	@ Enable access faults on domains 0 & 1
+	mov r0, #0x55	@ 01010101b
+	mcr p15, 0, r0, c3, c0, 0
+
+	@
+	@ Check for security extensions
+	@
+	mrc p15, 0, r0, c0, c1, 1
+	and r0, #0xF0
+	@ - Present
+	ldrne r0,=KERNEL_BASE
+	mcrne p15, 0, r0, c12, c0, 0	@ Set the VBAR (brings exceptions into high memory)
+	@ - Absent
+	mrceq p15, 0, r0, c1, c0, 0	@ Set SCTLR.V
+	orreq r0, #0x2000
+	mcreq p15, 0, r0, c1, c0, 0
+
+
+	@ Prepare for interrupts
+	cps #18	@ IRQ Mode
+	ldr sp, =irqstack+0x1000	@ Set up stack
+	cps #23	@ Abort Mode
+	ldr sp, =abortstack+0x1000
+	cps #19
+
+	ldr sp, =0x80000000-4	@ Set up stack (top of user range)
 	ldr r0, =kmain
 	mov pc, r0
 1:	b 1b	@ Infinite loop
 _ptr_kmain:
 	.long kmain
 
-.comm stack, 0x10000	@ ; 64KiB Stack
+.comm irqstack, 0x1000	@ ; 4KiB Stack
+.comm abortstack, 0x1000	@ ; 4KiB Stack
 
-SyscallHandler:
-	b .
+.extern SyscallHandler
+SVC_Handler:
+@	sub lr, #4
+	srsdb sp!, #19	@ Save state to stack
+	cpsie ifa, #19	@ Ensure we're in supervisor with interrupts enabled (should already be there)
+	push {r0-r12}
+
+	ldr r4, [lr,#-4]
+	mvn r5, #0xFF000000
+	and r4, r5
+
+	tst r4, #0x1000 
+	bne .arm_specifics
 
+	push {r4}
+
+	mov r0, sp
+	ldr r4, =SyscallHandler
+	blx r4
+	
+	ldr r0, =csSyscallPrintRetAddr
+	ldr r1, [sp,#9*4+5*4]
+	ldr r4, =Log
+	blx r4
+	
+	pop {r2}	@ errno
+	pop {r0,r1}	@ Ret/RetHi
+	add sp, #2*4	@ Saved r2/r3
+
+	pop {r4-r12}
+	rfeia sp!	@ Pop state (actually RFEFD)
+.arm_specifics:
+	and r4, #0xFF
+	mov r0, r4	@ Number
+	mov r1, sp	@ Arguments
+	
+	ldr r4, =ARMv7_int_HandleSyscalls
+	blx r4
+
+	add sp, #4*4
+	pop {r4-r12}
+	rfeia sp!
+
+
+.globl gpIRQHandler
+gpIRQHandler:	.long	0
+IRQ_saved_sp:	.long	0
+IRQ_saved_lr: 	.long	0
+.globl IRQHandler
 IRQHandler:
+	sub lr, #4	@ Adjust LR to the correct value
+	srsdb sp!, #19	@ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
+	cps #19
+
+	PUSH_GPRS
+
+	ldr r0, =csIRQ_Tag
+	ldr r1, =csIRQ_Fmt
+	ldr r4, =Log_Debug
+	blx r4
+	
+	@ Call the registered handler
+	ldr r0, gpIRQHandler
+	blx r0
+
+	@ Restore CPU state
+	POP_GPRS
+	cpsie i
+	rfeia sp!	@ Pop state (actually RFEFD)
+	bx lr
+
+.globl DataAbort
+DataAbort:
+	sub lr, #8	@ Adjust LR to the correct value
+	srsdb sp!, #23	@ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
+@	cpsid ifa, #19
+	PUSH_GPRS
+
+	mov r3, #0	@ not a prefetch abort
+	mrc p15, 0, r2, c5, c0, 0	@ Read DFSR (Data Fault Status Register) to R2
+	mrc p15, 0, r1, c6, c0, 0	@ Read DFAR (Data Fault Address Register) into R1
+	mov r0, lr	@ PC
+	ldr r4, =MM_PageFault
+	blx r4
+
+	POP_GPRS
+	rfeia sp!	@ Pop state (actually RFEFD)
+
+.globl PrefetchAbort
+PrefetchAbort:
+	sub lr, #4	@ Adjust LR to the correct value
+@	srsdb sp!, #19	@ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
+@	cpsid ifa, #19
+@	PUSH_GPRS
+
+	ldr r0, =csAbort_Tag
+	ldr r1, =csPrefetchAbort_Fmt
+	mov r2, lr
+	mrc p15, 0, r3, c5, c0, 0	@ Read IFSR (Instruction Fault Address Register) into R3
+	ldr r4, =Log_Error
+	blx r4
 	b .
 
+.section .rodata
+csIRQ_Tag:
+csAbort_Tag:
+	.asciz "ARMv7"
+csIRQ_Fmt:
+	.asciz "IRQ"
+csDataAbort_Fmt:
+	.asciz "Data Abort - %p accessed %p, DFSR=%x Unk:%x Unk:%x"
+csPrefetchAbort_Fmt:
+	.asciz "Prefetch Abort at %p, IFSR=%x"
+csSyscallPrintRetAddr:
+	.asciz "Syscall ret to %p"
+
 .section .padata
 .globl kernel_table0
 
 kernel_table0:
-	.long 0x00000002	@ Identity map the first 1 MiB
+	.long 0x00000402	@ Identity map the first 1 MiB
 	.rept 0x7FC - 1
 		.long 0
 	.endr
-	.long user_table1_map + 0x000 - KERNEL_BASE + 1
-	.long user_table1_map + 0x400 - KERNEL_BASE + 1
-	.long 0	@ user_table1_map + 0x800 - KERNEL_BASE + 1
-	.long 0	@ user_table1_map + 0xC00 - KERNEL_BASE + 1
+	.long user_table1_map + 0x000 - KERNEL_BASE + 1	@ 0x7FC00000
+	.long user_table1_map + 0x400 - KERNEL_BASE + 1	@ 0x7FD00000
+	.long user_table1_map + 0x800 - KERNEL_BASE + 1	@ KStacks
+	.long user_table1_map + 0xC00 - KERNEL_BASE + 1
 	@ 0x80000000 - User/Kernel split
-	.long 0x00000002	@ Map first 4 MiB to 2GiB
-	.long 0x00100002	@ 
-	.long 0x00200002	@ 
-	.long 0x00300002	@ 
+	.long 0x00000402	@ Map first 4 MiB to 2GiB (KRW only)
+	.long 0x00100402 	@ 
+	.long 0x00200402	@ 
+	.long 0x00300402	@ 
 	.rept 0xF00 - 0x800 - 4
 		.long 0
 	.endr
 #if PCI_PADDR
-	.long PCI_PADDR +  0*(1 << 20) + 2	@ Map PCI config space
-	.long PCI_PADDR +  1*(1 << 20) + 2
-	.long PCI_PADDR +  2*(1 << 20) + 2
-	.long PCI_PADDR +  3*(1 << 20) + 2
-	.long PCI_PADDR +  4*(1 << 20) + 2
-	.long PCI_PADDR +  5*(1 << 20) + 2
-	.long PCI_PADDR +  6*(1 << 20) + 2
-	.long PCI_PADDR +  7*(1 << 20) + 2
-	.long PCI_PADDR +  8*(1 << 20) + 2
-	.long PCI_PADDR +  9*(1 << 20) + 2
-	.long PCI_PADDR + 10*(1 << 20) + 2
-	.long PCI_PADDR + 11*(1 << 20) + 2
-	.long PCI_PADDR + 12*(1 << 20) + 2
-	.long PCI_PADDR + 13*(1 << 20) + 2
-	.long PCI_PADDR + 14*(1 << 20) + 2
-	.long PCI_PADDR + 15*(1 << 20) + 2
+	.long PCI_PADDR +  0*(1 << 20) + 0x402	@ Map PCI config space
+	.long PCI_PADDR +  1*(1 << 20) + 0x402
+	.long PCI_PADDR +  2*(1 << 20) + 0x402
+	.long PCI_PADDR +  3*(1 << 20) + 0x402
+	.long PCI_PADDR +  4*(1 << 20) + 0x402
+	.long PCI_PADDR +  5*(1 << 20) + 0x402
+	.long PCI_PADDR +  6*(1 << 20) + 0x402
+	.long PCI_PADDR +  7*(1 << 20) + 0x402
+	.long PCI_PADDR +  8*(1 << 20) + 0x402
+	.long PCI_PADDR +  9*(1 << 20) + 0x402
+	.long PCI_PADDR + 10*(1 << 20) + 0x402
+	.long PCI_PADDR + 11*(1 << 20) + 0x402
+	.long PCI_PADDR + 12*(1 << 20) + 0x402
+	.long PCI_PADDR + 13*(1 << 20) + 0x402
+	.long PCI_PADDR + 14*(1 << 20) + 0x402
+	.long PCI_PADDR + 15*(1 << 20) + 0x402
 #else
 	.rept 16
 		.long 0
@@ -101,41 +239,67 @@ kernel_table0:
 	.long kernel_table1_map + 0x400 - KERNEL_BASE + 1
 	.long kernel_table1_map + 0x800 - KERNEL_BASE + 1
 	.long kernel_table1_map + 0xC00 - KERNEL_BASE + 1
-	@ Top level fractals
-	.long 0 	@ removed for alignment constraints, using the KERNEL_BASE identity mapping instead
-	.rept 0x1000 - 0xFF8 - 5
-		.long 0
-	.endr
+	.long kernel_exception_map + 0x000 - KERNEL_BASE + 1
+	.long kernel_exception_map + 0x400 - KERNEL_BASE + 1
+	.long kernel_exception_map + 0x800 - KERNEL_BASE + 1
+	.long kernel_exception_map + 0xC00 - KERNEL_BASE + 1
 
 @ PID0 user table
 .globl user_table1_map
-user_table1_map:	@ Size = 4KiB
-	.rept 0x7F8/4
+@ User table1 data table (only the first half is needed)
+@ - Abused to provide kernel stacks in the unused half of the table
+user_table1_map:	@ Size = 4KiB (only 2KiB used)
+	.rept 0x800/4-1
 		.long 0
 	.endr
-	.long kernel_table0 - KERNEL_BASE + (1 << 4) + 3
-	.long user_table1_map - KERNEL_BASE + (1 << 4) + 3
-	.rept 0x800/4
+	.long user_table1_map - KERNEL_BASE + 0x13  	@ ...1FF000 = 0x7FDFF000
+	@ Kernel stack zone
+	.long kernel_table0 + 0x0000 - KERNEL_BASE + 0x13	@ ...200000 = 0x7FE00000
+	.long kernel_table0 + 0x1000 - KERNEL_BASE + 0x13	@ ...201000 = 0x7FE01000
+	.rept (0x800/4)-(MM_KSTACK_SIZE/0x1000)-2
 		.long 0
 	.endr
+	#if MM_KSTACK_SIZE != 0x2000
+	#error Kernel stack size not changed in start.S
+	#endif
+	.long stack + 0x0000 - KERNEL_BASE + 0x13	@ Kernel Stack
+	.long stack + 0x1000 - KERNEL_BASE + 0x13	@ 
 
 .globl kernel_table1_map
 kernel_table1_map:	@ Size = 4KiB
-	.rept 0xF00/4
+	.rept (0xF00+16)/4
 		.long 0
 	.endr
 	.long hwmap_table_0 - KERNEL_BASE + (1 << 4) + 3
-	.rept 0xFF8/4 - 0xF00/4 - 1
+	.rept 0xFF8/4 - (0xF00+16)/4 - 1
 		.long 0
 	.endr
-	.long kernel_table1_map - KERNEL_BASE + (1 << 4) + 3
-	.long 0
+	.long kernel_table1_map - KERNEL_BASE + 0x13
+	.long kernel_exception_map - KERNEL_BASE + 0x13
 
 @ Hardware mappings 
 .globl hwmap_table_0
 hwmap_table_0:
-	.long UART0_PADDR + (1 << 4) + 3	@ UART0
+	.long UART0_PADDR + 0x13	@ UART0
 	.rept 1024 - 1
 		.long 0
 	.endr
+.globl kernel_exception_map
+kernel_exception_map:
+	@ Padding
+	.rept 1024-256
+		.long 0
+	.endr
+	@ Align to nearly the end
+	.rept 256-16
+		.long	0
+	.endr
+	.long 0x212	@ Map first page for exceptions (Kernel RO, Execute)
+	.rept 15
+		.long 0
+	.endr
 	
+.section .padata
+stack:
+	.space MM_KSTACK_SIZE, 0	@ Original kernel stack
+