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, =kernel_table0-KERNEL_BASE
22 mcr p15, 0, r0, c2, c0, 1 @ Set TTBR1 to r0
23 mcr p15, 0, r0, c2, c0, 0 @ Set TTBR0 to r0 too (for identity)
26 mcr p15, 0, r0, c2, c0, 2 @ Set TTCR to 1 (50/50 split)
29 mcr p15, 0, r0, c3, c0, 0 @ Set Domain 0 to Manager
32 mrc p15, 0, r0, c1, c0, 0
35 mcr p15, 0, r0, c1, c0, 0
37 @ Enable access faults on domains 0 & 1
38 mov r0, #0x55 @ 01010101b
39 mcr p15, 0, r0, c3, c0, 0
42 @ Check for security extensions
44 mrc p15, 0, r0, c0, c1, 1
48 mcrne p15, 0, r0, c12, c0, 0 @ Set the VBAR (brings exceptions into high memory)
50 mrceq p15, 0, r0, c1, c0, 0 @ Set SCTLR.V
52 mcreq p15, 0, r0, c1, c0, 0
55 @ Prepare for interrupts
57 ldr sp, =irqstack+0x1000 @ Set up stack
59 ldr sp, =abortstack+0x1000
62 ldr sp, =0x80000000-4 @ Set up stack (top of user range)
65 1: b 1b @ Infinite loop
69 .comm irqstack, 0x1000 @ ; 4KiB Stack
70 .comm abortstack, 0x1000 @ ; 4KiB Stack
72 .extern SyscallHandler
75 srsdb sp!, #19 @ Save state to stack
76 cpsie ifa, #19 @ Ensure we're in supervisor with interrupts enabled (should already be there)
89 ldr r4, =SyscallHandler
92 @ ldr r0, =csSyscallPrintRetAddr
93 @ ldr r1, [sp,#9*4+5*4]
98 pop {r0,r1} @ Ret/RetHi
99 add sp, #2*4 @ Saved r2/r3
102 rfeia sp! @ Pop state (actually RFEFD)
106 mov r1, sp @ Arguments
108 ldr r4, =ARMv7_int_HandleSyscalls
117 gpIRQHandler: .long 0
118 IRQ_saved_sp: .long 0
119 IRQ_saved_lr: .long 0
122 sub lr, #4 @ Adjust LR to the correct value
123 srsdb sp!, #19 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
133 @ Call the registered handler
140 rfeia sp! @ Pop state (actually RFEFD)
145 sub lr, #8 @ Adjust LR to the correct value
146 srsdb sp!, #23 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
150 mov r3, #0 @ not a prefetch abort
151 mrc p15, 0, r2, c5, c0, 0 @ Read DFSR (Data Fault Status Register) to R2
152 mrc p15, 0, r1, c6, c0, 0 @ Read DFAR (Data Fault Address Register) into R1
154 ldr r4, =MM_PageFault
158 rfeia sp! @ Pop state (actually RFEFD)
162 sub lr, #4 @ Adjust LR to the correct value
163 @ srsdb sp!, #19 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
168 ldr r1, =csPrefetchAbort_Fmt
170 mrc p15, 0, r3, c5, c0, 0 @ Read IFSR (Instruction Fault Address Register) into R3
182 .asciz "Data Abort - %p accessed %p, DFSR=%x Unk:%x Unk:%x"
184 .asciz "Prefetch Abort at %p, IFSR=%x"
185 csSyscallPrintRetAddr:
186 .asciz "Syscall ret to %p"
192 .long 0x00000402 @ Identity map the first 1 MiB
196 .long user_table1_map + 0x000 - KERNEL_BASE + 1 @ 0x7FC00000
197 .long user_table1_map + 0x400 - KERNEL_BASE + 1 @ 0x7FD00000
198 .long user_table1_map + 0x800 - KERNEL_BASE + 1 @ KStacks
199 .long user_table1_map + 0xC00 - KERNEL_BASE + 1
200 @ 0x80000000 - User/Kernel split
201 .long 0x00000402 @ Map first 4 MiB to 2GiB (KRW only)
205 .rept 0xF00 - 0x800 - 4
209 .long PCI_PADDR + 0*(1 << 20) + 0x402 @ Map PCI config space
210 .long PCI_PADDR + 1*(1 << 20) + 0x402
211 .long PCI_PADDR + 2*(1 << 20) + 0x402
212 .long PCI_PADDR + 3*(1 << 20) + 0x402
213 .long PCI_PADDR + 4*(1 << 20) + 0x402
214 .long PCI_PADDR + 5*(1 << 20) + 0x402
215 .long PCI_PADDR + 6*(1 << 20) + 0x402
216 .long PCI_PADDR + 7*(1 << 20) + 0x402
217 .long PCI_PADDR + 8*(1 << 20) + 0x402
218 .long PCI_PADDR + 9*(1 << 20) + 0x402
219 .long PCI_PADDR + 10*(1 << 20) + 0x402
220 .long PCI_PADDR + 11*(1 << 20) + 0x402
221 .long PCI_PADDR + 12*(1 << 20) + 0x402
222 .long PCI_PADDR + 13*(1 << 20) + 0x402
223 .long PCI_PADDR + 14*(1 << 20) + 0x402
224 .long PCI_PADDR + 15*(1 << 20) + 0x402
230 .long hwmap_table_0 + 0x000 - KERNEL_BASE + 1
231 .long hwmap_table_0 + 0x400 - KERNEL_BASE + 1
232 .long hwmap_table_0 + 0x800 - KERNEL_BASE + 1
233 .long hwmap_table_0 + 0xC00 - KERNEL_BASE + 1
234 .rept 0xFF8 - 0xF00 - 16 - 4
238 .long kernel_table1_map + 0x000 - KERNEL_BASE + 1
239 .long kernel_table1_map + 0x400 - KERNEL_BASE + 1
240 .long kernel_table1_map + 0x800 - KERNEL_BASE + 1
241 .long kernel_table1_map + 0xC00 - KERNEL_BASE + 1
242 .long kernel_exception_map + 0x000 - KERNEL_BASE + 1
243 .long kernel_exception_map + 0x400 - KERNEL_BASE + 1
244 .long kernel_exception_map + 0x800 - KERNEL_BASE + 1
245 .long kernel_exception_map + 0xC00 - KERNEL_BASE + 1
248 .globl user_table1_map
249 @ User table1 data table (only the first half is needed)
250 @ - Abused to provide kernel stacks in the unused half of the table
251 user_table1_map: @ Size = 4KiB (only 2KiB used)
255 .long user_table1_map - KERNEL_BASE + 0x13 @ ...1FF000 = 0x7FDFF000
257 .long kernel_table0 + 0x0000 - KERNEL_BASE + 0x13 @ ...200000 = 0x7FE00000
258 .long kernel_table0 + 0x1000 - KERNEL_BASE + 0x13 @ ...201000 = 0x7FE01000
259 .rept (0x800/4)-(MM_KSTACK_SIZE/0x1000)-2
262 #if MM_KSTACK_SIZE != 0x2000
263 #error Kernel stack size not changed in start.S
265 .long stack + 0x0000 - KERNEL_BASE + 0x13 @ Kernel Stack
266 .long stack + 0x1000 - KERNEL_BASE + 0x13 @
268 .globl kernel_table1_map
269 kernel_table1_map: @ Size = 4KiB
273 .long hwmap_table_0 - KERNEL_BASE + 0x13
274 .rept 0xFF8/4 - (0xF00+16)/4 - 1
277 .long kernel_table1_map - KERNEL_BASE + 0x13
278 .long kernel_exception_map - KERNEL_BASE + 0x13
283 .long UART0_PADDR + 0x13 @ UART0
287 .globl kernel_exception_map
288 kernel_exception_map:
293 @ Align to nearly the end
297 .long 0x212 @ Map first page for exceptions (Kernel RO, Execute)
301 .long gUsertextPhysStart + 0x22 @ User .text (User RO, Kernel RW, because both is COW)
306 .space MM_KSTACK_SIZE, 0 @ Original kernel stack