2 #include "include/assembly.h"
3 #include "include/options.h"
6 @ Exception defs taken from ARM DDI 0406B
9 interrupt_vector_table:
10 ivt_reset: b _start @ 0x00 Reset
11 ivt_undef: b . @ 0x04 #UD
12 ivt_svc: b SVC_Handler @ 0x08 SVC (used to be called SWI)
13 ivt_prefetch: b PrefetchAbort @ 0x0C Prefetch abort
14 ivt_data: b DataAbort @ 0x10 Data abort
15 ivt_unused: b . @ 0x14 Not Used
16 ivt_irq: b IRQHandler @ 0x18 IRQ
17 ivt_fiq: b . @ 0x1C FIQ (Fast interrupt)
21 ldr r0, =DEBUG_UART_PADDR
25 ldr r0, =kernel_table0-KERNEL_BASE
26 mcr p15, 0, r0, c2, c0, 1 @ Set TTBR1 to r0
27 mcr p15, 0, r0, c2, c0, 0 @ Set TTBR0 to r0 too (for identity)
30 mcr p15, 0, r0, c2, c0, 2 @ Set TTCR to 1 (50/50 split)
33 mcr p15, 0, r0, c3, c0, 0 @ Set Domain 0 to Manager
36 mrc p15, 0, r0, c1, c0, 0
39 mcr p15, 0, r0, c1, c0, 0
41 @ Enable access faults on domains 0 & 1
42 mov r0, #0x55 @ 01010101b
43 mcr p15, 0, r0, c3, c0, 0
46 @ Check for security extensions
48 mrc p15, 0, r0, c0, c1, 1
52 mcrne p15, 0, r0, c12, c0, 0 @ Set the VBAR (brings exceptions into high memory)
54 mrceq p15, 0, r0, c1, c0, 0 @ Set SCTLR.V
56 mcreq p15, 0, r0, c1, c0, 0
59 @ Prepare for interrupts
61 ldr sp, =irqstack+0x1000 @ Set up stack
63 ldr sp, =abortstack+0x1000
66 ldr sp, =0x80000000-4 @ Set up stack (top of user range)
69 1: b 1b @ Infinite loop
73 .comm irqstack, 0x1000 @ ; 4KiB Stack
74 .comm abortstack, 0x1000 @ ; 4KiB Stack
76 .extern SyscallHandler
79 srsdb sp!, #19 @ Save state to stack
80 cpsie ifa, #19 @ Ensure we're in supervisor with interrupts enabled (should already be there)
93 ldr r4, =SyscallHandler
96 @ ldr r0, =csSyscallPrintRetAddr
97 @ ldr r1, [sp,#9*4+5*4]
102 pop {r0,r1} @ Ret/RetHi
103 add sp, #2*4 @ Saved r2/r3
106 rfeia sp! @ Pop state (actually RFEFD)
110 mov r1, sp @ Arguments
112 ldr r4, =ARMv7_int_HandleSyscalls
121 gpIRQHandler: .long 0
122 IRQ_saved_sp: .long 0
123 IRQ_saved_lr: .long 0
126 sub lr, #4 @ Adjust LR to the correct value
127 srsdb sp!, #19 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
137 @ Call the registered handler
144 rfeia sp! @ Pop state (actually RFEFD)
149 sub lr, #8 @ Adjust LR to the correct value
150 srsdb sp!, #23 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
154 mov r3, #0 @ not a prefetch abort
155 mrc p15, 0, r2, c5, c0, 0 @ Read DFSR (Data Fault Status Register) to R2
156 mrc p15, 0, r1, c6, c0, 0 @ Read DFAR (Data Fault Address Register) into R1
158 ldr r4, =MM_PageFault
162 rfeia sp! @ Pop state (actually RFEFD)
166 sub lr, #4 @ Adjust LR to the correct value
167 @ srsdb sp!, #19 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
172 ldr r1, =csPrefetchAbort_Fmt
174 mrc p15, 0, r3, c5, c0, 0 @ Read IFSR (Instruction Fault Address Register) into R3
186 .asciz "Data Abort - %p accessed %p, DFSR=%x Unk:%x Unk:%x"
188 .asciz "Prefetch Abort at %p, IFSR=%x"
189 csSyscallPrintRetAddr:
190 .asciz "Syscall ret to %p"
196 .long 0x00000402 @ Identity map the first 1 MiB
200 .long user_table1_map + 0x000 - KERNEL_BASE + 1 @ 0x7FC00000
201 .long user_table1_map + 0x400 - KERNEL_BASE + 1 @ 0x7FD00000
202 .long user_table1_map + 0x800 - KERNEL_BASE + 1 @ KStacks
203 .long user_table1_map + 0xC00 - KERNEL_BASE + 1
204 @ 0x80000000 - User/Kernel split
205 .long 0x00000402 @ Map first 4 MiB to 2GiB (KRW only)
209 .rept 0xF00 - 0x800 - 4
213 .long PCI_PADDR + 0*(1 << 20) + 0x402 @ Map PCI config space
214 .long PCI_PADDR + 1*(1 << 20) + 0x402
215 .long PCI_PADDR + 2*(1 << 20) + 0x402
216 .long PCI_PADDR + 3*(1 << 20) + 0x402
217 .long PCI_PADDR + 4*(1 << 20) + 0x402
218 .long PCI_PADDR + 5*(1 << 20) + 0x402
219 .long PCI_PADDR + 6*(1 << 20) + 0x402
220 .long PCI_PADDR + 7*(1 << 20) + 0x402
221 .long PCI_PADDR + 8*(1 << 20) + 0x402
222 .long PCI_PADDR + 9*(1 << 20) + 0x402
223 .long PCI_PADDR + 10*(1 << 20) + 0x402
224 .long PCI_PADDR + 11*(1 << 20) + 0x402
225 .long PCI_PADDR + 12*(1 << 20) + 0x402
226 .long PCI_PADDR + 13*(1 << 20) + 0x402
227 .long PCI_PADDR + 14*(1 << 20) + 0x402
228 .long PCI_PADDR + 15*(1 << 20) + 0x402
234 .long hwmap_table_0 + 0x000 - KERNEL_BASE + 1
235 .long hwmap_table_0 + 0x400 - KERNEL_BASE + 1
236 .long hwmap_table_0 + 0x800 - KERNEL_BASE + 1
237 .long hwmap_table_0 + 0xC00 - KERNEL_BASE + 1
238 .rept 0xFF8 - 0xF00 - 16 - 4
242 .long kernel_table1_map + 0x000 - KERNEL_BASE + 1
243 .long kernel_table1_map + 0x400 - KERNEL_BASE + 1
244 .long kernel_table1_map + 0x800 - KERNEL_BASE + 1
245 .long kernel_table1_map + 0xC00 - KERNEL_BASE + 1
246 .long kernel_exception_map + 0x000 - KERNEL_BASE + 1
247 .long kernel_exception_map + 0x400 - KERNEL_BASE + 1
248 .long kernel_exception_map + 0x800 - KERNEL_BASE + 1
249 .long kernel_exception_map + 0xC00 - KERNEL_BASE + 1
252 .globl user_table1_map
253 @ User table1 data table (only the first half is needed)
254 @ - Abused to provide kernel stacks in the unused half of the table
255 user_table1_map: @ Size = 4KiB (only 2KiB used)
259 .long user_table1_map - KERNEL_BASE + 0x13 @ ...1FF000 = 0x7FDFF000
261 .long kernel_table0 + 0x0000 - KERNEL_BASE + 0x13 @ ...200000 = 0x7FE00000
262 .long kernel_table0 + 0x1000 - KERNEL_BASE + 0x13 @ ...201000 = 0x7FE01000
263 .rept (0x800/4)-(MM_KSTACK_SIZE/0x1000)-2
266 #if MM_KSTACK_SIZE != 0x2000
267 #error Kernel stack size not changed in start.S
269 .long stack + 0x0000 - KERNEL_BASE + 0x13 @ Kernel Stack
270 .long stack + 0x1000 - KERNEL_BASE + 0x13 @
272 .globl kernel_table1_map
273 kernel_table1_map: @ Size = 4KiB
277 .long hwmap_table_0 - KERNEL_BASE + 0x13
278 .rept 0xFF8/4 - (0xF00+16)/4 - 1
281 .long kernel_table1_map - KERNEL_BASE + 0x13
282 .long kernel_exception_map - KERNEL_BASE + 0x13
287 .long UART0_PADDR + 0x13 @ UART0
291 .globl kernel_exception_map
292 kernel_exception_map:
297 @ Align to nearly the end
301 .long 0x212 @ Map first page for exceptions (Kernel RO, Execute)
305 .long gUsertextPhysStart + 0x22 @ User .text (User RO, Kernel RW, because both is COW)
310 .space MM_KSTACK_SIZE, 0 @ Original kernel stack
312 ; vim: ts=8, ft=armv7