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)
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)
33 mcr p15, 0, r0, c2, c0, 2 @ Set TTCR to 1 (50/50 split)
39 mcr p15, 0, r0, c3, c0, 0 @ Set Domain 0 to Manager
45 mrc p15, 0, r0, c1, c0, 0
48 mcr p15, 0, r0, c1, c0, 0
54 @ Enable access faults on domains 0 & 1
55 mov r0, #0x55 @ 01010101b
56 mcr p15, 0, r0, c3, c0, 0
62 @ Check for security extensions
64 mrc p15, 0, r0, c0, c1, 1
68 mcrne p15, 0, r0, c12, c0, 0 @ Set the VBAR (brings exceptions into high memory)
70 mrceq p15, 0, r0, c1, c0, 0 @ Set SCTLR.V
72 mcreq p15, 0, r0, c1, c0, 0
77 @ Prepare for interrupts
79 ldr sp, =irqstack+0x1000 @ Set up stack
81 ldr sp, =abortstack+0x1000
96 .extern bss_size_div_4
107 ldr sp, =0x80000000-8 @ Set up stack (top of user range)
110 1: b 1b @ Infinite loop
112 .comm irqstack, 0x1000 @ ; 4KiB Stack
113 .comm abortstack, 0x1000 @ ; 4KiB Stack
115 .extern SyscallHandler
118 srsdb sp!, #19 @ Save state to stack
119 cpsie ifa, #19 @ Ensure we're in supervisor with interrupts enabled (should already be there)
132 ldr r4, =SyscallHandler
135 @ ldr r0, =csSyscallPrintRetAddr
136 @ ldr r1, [sp,#9*4+5*4]
141 pop {r0,r1} @ Ret/RetHi
142 add sp, #2*4 @ Saved r2/r3
145 rfeia sp! @ Pop state (actually RFEFD)
149 mov r1, sp @ Arguments
151 ldr r4, =ARMv7_int_HandleSyscalls
160 gpIRQHandler: .long 0
161 IRQ_saved_sp: .long 0
162 IRQ_saved_lr: .long 0
165 sub lr, #4 @ Adjust LR to the correct value
166 srsdb sp!, #19 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
176 @ Call the registered handler
183 rfeia sp! @ Pop state (actually RFEFD)
188 sub lr, #8 @ Adjust LR to the correct value
189 srsdb sp!, #23 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
193 mov r3, #0 @ not a prefetch abort
194 mrc p15, 0, r2, c5, c0, 0 @ Read DFSR (Data Fault Status Register) to R2
195 mrc p15, 0, r1, c6, c0, 0 @ Read DFAR (Data Fault Address Register) into R1
197 ldr r4, =MM_PageFault
201 rfeia sp! @ Pop state (actually RFEFD)
205 sub lr, #4 @ Adjust LR to the correct value
206 srsdb sp!, #23 @ Switch to supervisor mode (DDI0406B D1.6.5) (actually SRSFD)
211 ldr r1, =csPrefetchAbort_Fmt
213 mrc p15, 0, r2, c6, c0, 2 @ Read IFAR (Instruction Fault Address Register) into R3
214 mrc p15, 0, r3, c5, c0, 1 @ Read IFSR (Instruction Fault Status Register) into R3
227 .asciz "Data Abort - %p accessed %p, DFSR=%x Unk:%x Unk:%x"
229 .asciz "Prefetch Abort at %p, IFSR=%x"
230 csSyscallPrintRetAddr:
231 .asciz "Syscall ret to %p"
237 .long 0x00000402 @ Identity map the first 1 MiB
241 .long user_table1_map + 0x000 - KERNEL_BASE + 1 @ 0x7FC00000
242 .long user_table1_map + 0x400 - KERNEL_BASE + 1 @ 0x7FD00000
243 .long user_table1_map + 0x800 - KERNEL_BASE + 1 @ KStacks
244 .long user_table1_map + 0xC00 - KERNEL_BASE + 1
245 @ 0x80000000 - User/Kernel split
246 .long 0x00000402 @ Map first 4 MiB to 2GiB (KRW only)
250 .rept 0xF00 - 0x800 - 4
254 .long PCI_PADDR + 0*(1 << 20) + 0x402 @ Map PCI config space
255 .long PCI_PADDR + 1*(1 << 20) + 0x402
256 .long PCI_PADDR + 2*(1 << 20) + 0x402
257 .long PCI_PADDR + 3*(1 << 20) + 0x402
258 .long PCI_PADDR + 4*(1 << 20) + 0x402
259 .long PCI_PADDR + 5*(1 << 20) + 0x402
260 .long PCI_PADDR + 6*(1 << 20) + 0x402
261 .long PCI_PADDR + 7*(1 << 20) + 0x402
262 .long PCI_PADDR + 8*(1 << 20) + 0x402
263 .long PCI_PADDR + 9*(1 << 20) + 0x402
264 .long PCI_PADDR + 10*(1 << 20) + 0x402
265 .long PCI_PADDR + 11*(1 << 20) + 0x402
266 .long PCI_PADDR + 12*(1 << 20) + 0x402
267 .long PCI_PADDR + 13*(1 << 20) + 0x402
268 .long PCI_PADDR + 14*(1 << 20) + 0x402
269 .long PCI_PADDR + 15*(1 << 20) + 0x402
275 .long hwmap_table_0 + 0x000 - KERNEL_BASE + 1
276 .long hwmap_table_0 + 0x400 - KERNEL_BASE + 1
277 .long hwmap_table_0 + 0x800 - KERNEL_BASE + 1
278 .long hwmap_table_0 + 0xC00 - KERNEL_BASE + 1
279 .rept 0xFF8 - 0xF00 - 16 - 4
283 .long kernel_table1_map + 0x000 - KERNEL_BASE + 1
284 .long kernel_table1_map + 0x400 - KERNEL_BASE + 1
285 .long kernel_table1_map + 0x800 - KERNEL_BASE + 1
286 .long kernel_table1_map + 0xC00 - KERNEL_BASE + 1
287 .long kernel_exception_map + 0x000 - KERNEL_BASE + 1
288 .long kernel_exception_map + 0x400 - KERNEL_BASE + 1
289 .long kernel_exception_map + 0x800 - KERNEL_BASE + 1
290 .long kernel_exception_map + 0xC00 - KERNEL_BASE + 1
293 .globl user_table1_map
294 @ User table1 data table (only the first half is needed)
295 @ - Abused to provide kernel stacks in the unused half of the table
296 user_table1_map: @ Size = 4KiB (only 2KiB used)
300 .long user_table1_map - KERNEL_BASE + 0x13 @ ...1FF000 = 0x7FDFF000
302 .long kernel_table0 + 0x0000 - KERNEL_BASE + 0x13 @ ...200000 = 0x7FE00000
303 .long kernel_table0 + 0x1000 - KERNEL_BASE + 0x13 @ ...201000 = 0x7FE01000
304 .rept (0x800/4)-(MM_KSTACK_SIZE/0x1000)-2
307 #if MM_KSTACK_SIZE != 0x2000
308 #error Kernel stack size not changed in start.S
310 .long stack + 0x0000 - KERNEL_BASE + 0x13 @ Kernel Stack
311 .long stack + 0x1000 - KERNEL_BASE + 0x13 @
313 .globl kernel_table1_map
314 kernel_table1_map: @ Size = 4KiB
318 .long hwmap_table_0 - KERNEL_BASE + 0x13
319 .rept 0xFF8/4 - (0xF00+16)/4 - 1
322 .long kernel_table1_map - KERNEL_BASE + 0x13
323 .long kernel_exception_map - KERNEL_BASE + 0x13
328 .long UART0_PADDR + 0x13 @ UART0
332 .globl kernel_exception_map
333 kernel_exception_map:
338 @ Align to nearly the end
342 .long 0x212 @ Map first page for exceptions (Kernel RO, Execute)
346 .long gUsertextPhysStart + 0x22 @ User .text (User RO, Kernel RW, because both is COW)
351 .space MM_KSTACK_SIZE, 0 @ Original kernel stack
353 // vim: ts=8 ft=armv7