Code reformat/cleanup of exception_vectors.S
This commit is contained in:
Alex Stewart
parent
b6c2e4df59
commit
b813489524
1 changed files with 506 additions and 467 deletions
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@ -1,334 +1,34 @@
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/* Xtensa Exception (ie interrupt) Vectors & low-level handler code
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Core exception handler code is placed in the .vecbase section,
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which gets picked up specially in the linker script and placed
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at beginning of IRAM.
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The actual VecBase symbol should be the first thing in .vecbase
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(this is not strictly important as it gets set by symbol lookup not
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by hardcoded address, but having it at 0x40100000 means that the
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exception vectors have memorable offsets, which match the default
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Boot ROM vector offsets. So convenient for human understanding.
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Part of esp-open-rtos
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Original vector contents Copyright (C) 2014-2015 Espressif Systems
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Additions Copyright (C) Superhouse Automation Pty Ltd and Angus Gratton
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BSD Licensed as described in the file LICENSE
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*/
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*
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* Core exception handler code is placed in the .vecbase section, which gets
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* picked up specially in the linker script and placed at beginning of IRAM.
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*
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* The actual VecBase symbol should be the first thing in .vecbase (this is not
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* strictly important as it gets set by symbol lookup not by hardcoded address,
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* but having it at 0x40100000 means that the exception vectors have memorable
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* offsets, which match the default Boot ROM vector offsets. So convenient for
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* human understanding.
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*
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* Part of esp-open-rtos
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* Original vector contents Copyright (C) 2014-2015 Espressif Systems
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* Additions Copyright (C) Superhouse Automation Pty Ltd and Angus Gratton
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* BSD Licensed as described in the file LICENSE
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*/
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#include "led_debug.s"
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/* Some UserException causes, see table Table 4–64 in ISA reference */
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#define CAUSE_SYSCALL 1
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#define CAUSE_LOADSTORE 3
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#define CAUSE_LVL1INT 4
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.text
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.section .vecbase.text, "x"
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.global VecBase
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.org 0
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VecBase:
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/* IMPORTANT: exception vector literals will go here, but we
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can't have more than 4 otherwise we push DebugExceptionVector past
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offset 0x10 relative to VecBase. There should be ways to avoid this,
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and also keep the VecBase offsets easy to read, but this works for now.
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*/
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.literal_position
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.org 0x10
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.type DebugExceptionVector, @function
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DebugExceptionVector:
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wsr.excsave2 a0
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call0 sdk_user_fatal_exception_handler
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rfi 2
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.org 0x20
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.type NMIExceptionVector, @function
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NMIExceptionVector:
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wsr.excsave3 a0
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call0 CallNMIExceptionHandler
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rfi 3 /* CallNMIExceptionHandler should call rfi itself */
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.org 0x30
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.type KernelExceptionVector, @function
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KernelExceptionVector:
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break 1, 0
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call0 sdk_user_fatal_exception_handler
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rfe
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.org 0x50
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.type UserExceptionVector, @function
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UserExceptionVector:
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wsr.excsave1 a1
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rsr.exccause a1
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beqi a1, CAUSE_LOADSTORE, LoadStoreErrorHandler
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j UserExceptionHandler
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.org 0x70
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.type DoubleExceptionVector, @function
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DoubleExceptionVector:
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break 1, 4
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call0 sdk_user_fatal_exception_handler
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/* Reset vector would go here at offset 0x80 but should be unused,
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as vecbase goes back to mask ROM vectors on reset */
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/***** end of exception vectors *****/
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/* Xtensa Exception unaligned load handler
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Completes l8/l16 load instructions from Instruction address space,
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for which the architecture only supports 32-bit reads.
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Called from UserExceptionVector if EXCCAUSE is LoadStoreErrorCause
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Fast path (no branches) is for l8ui.
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*/
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.literal_position
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.type LoadStoreErrorHandler, @function
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LoadStoreErrorHandler:
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# Note: registers are saved in the address corresponding to their
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# register number times 4. This allows a quick and easy mapping later
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# on when needing to store the value to a particular register number.
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movi sp, LoadStoreErrorHandlerStack
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s32i a0, sp, 0
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s32i a2, sp, 0x08
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s32i a3, sp, 0x0c
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s32i a4, sp, 0x10
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rsr.sar a0 # Save SAR in a0 to restore later
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# Examine the opcode which generated the exception
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# Note: Instructions are in this order to avoid pipeline stalls.
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rsr.epc1 a2
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movi a3, ~3
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ssa8l a2 // sar is now correct shift for aligned read
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and a2, a2, a3 // a2 now 4-byte aligned address of instruction
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l32i a4, a2, 0
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l32i a2, a2, 4
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movi a3, 0x00700F // opcode mask for l8ui/l16si/l16ui
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src a2, a2, a4 // a2 now instruction that failed
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and a3, a2, a3
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bnei a3, 0x000002, .LSE_check_l16
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# Note: At this point, opcode could technically be one of two things:
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# xx0xx2 (L8UI)
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# xx8xx2 (Reserved (invalid) opcode)
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# It is assumed that we'll never get to this point from an illegal
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# opcode, so we don't bother to check for that case and presume this is
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# always an L8UI.
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/* a2 holds instruction */
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movi a4, ~3
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rsr.excvaddr a3 // read faulting address
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and a4, a3, a4 /* a4 now word aligned read address */
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l32i a4, a4, 0 /* perform the actual read */
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ssa8l a3 /* sar is now shift to extract a3's byte */
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srl a3, a4 /* shift right correct distance */
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extui a4, a3, 0, 8 /* mask off bits we need for an l8 */
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.LSE_post_fetch:
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# We jump back here after either the L8UI or the L16*I routines do the
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# necessary work to read the value from memory.
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# At this point, a2 holds the faulting instruction and a4 holds the
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# correctly read value.
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# Restore original SAR value (saved in a0) and update EPC so we'll
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# return back to the instruction following the one we just emulated
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# Note: Instructions are in this order to avoid pipeline stalls
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rsr.epc1 a3
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wsr.sar a0
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addi a3, a3, 0x3
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wsr.epc1 a3
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# Stupid opcode tricks: The jumptable we use later on needs 16 bytes
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# per entry (so we can avoid a second jump by just doing a RFE inside
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# each entry). Unfortunately, however, Xtensa doesn't have an addx16
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# operation to make that easy for us. Luckily, all of the faulting
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# opcodes we're processing are guaranteed to have bit 3 be zero, which
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# means if we just shift the register bits of the opcode down by 3
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# instead of 4, we will get the register number multiplied by 2. This
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# combined with an addx8 will give us an effective addx16 without
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# needing any extra shift operations.
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extui a2, a2, 3, 5 /* a2 now destination register 0-15 times 2 */
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bgei a2, 10, .LSE_assign_reg # a5..a15 use jumptable
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beqi a2, 2, .LSE_assign_a1 # a1 uses a special routine
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# We're storing into a0 or a2..a4, which are all saved in our "stack" area.
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# Calculate the correct address and stick the value in there, then just
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# do our normal restore and RFE (no jumps required, which actually
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# makes a0..a4 substantially faster).
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addx2 a2, a2, sp
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s32i a4, a2, 0
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# Restore all regs and return
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l32i a0, sp, 0
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l32i a2, sp, 0x08
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l32i a3, sp, 0x0c
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l32i a4, sp, 0x10
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rsr.excsave1 a1 # restore a1 saved by UserExceptionVector
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rfe
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.LSE_assign_reg:
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# At this point, a2 contains the register number times 2, a4 is the
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# read value.
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# Calculate the jumptable address, and restore regs except a2 and a4
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# so we have less to do after jumping.
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# Note: Instructions are in this order to avoid pipeline stalls.
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movi a3, .LSE_jumptable_base
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l32i a0, sp, 0
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addx8 a2, a2, a3 # a2 is now the address to jump to
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l32i a3, sp, 0x0c
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jx a2
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/* Check the load instruction a2 for an l16si/16ui instruction
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a2 is the instruction, a3 is masked instruction */
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.balign 4
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.LSE_check_l16:
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movi a4, 0x001002 /* l16si or l16ui opcode after masking */
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bne a3, a4, .LSE_wrong_opcode
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# Note: At this point, the opcode could be one of two things:
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# xx1xx2 (L16UI)
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# xx9xx2 (L16SI)
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# Both of these we can handle.
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movi a4, ~3
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rsr.excvaddr a3 // read faulting address
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and a4, a3, a4 /* a4 now word aligned read address */
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l32i a4, a4, 0 /* perform the actual read */
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ssa8l a3 /* sar is now shift to extract a3's byte */
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srl a3, a4 /* shift right correct distance */
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extui a4, a3, 0, 16 /* mask off bits we need for an l16 */
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bbci a2, 15, .LSE_post_fetch # Not a signed op
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bbci a4, 15, .LSE_post_fetch # Value does not require sign-extension
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movi a3, 0xFFFF0000
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or a4, a3, a4 /* set 32-bit sign bits */
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j .LSE_post_fetch
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/* If we got here it's not an opcode we can try to fix, so bomb out */
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.LSE_wrong_opcode:
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# Restore registers so any dump the fatal exception routine produces
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# will have correct values
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wsr.sar a0 # Restore SAR saved in a0
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l32i a0, sp, 0
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l32i a2, sp, 0x08
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l32i a3, sp, 0x0c
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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call0 sdk_user_fatal_exception_handler
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.balign 4
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.LSE_assign_a1:
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# a1 is saved in excsave1, so just update that with the value
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wsr.excsave1 a4
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# Restore all regs and return
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l32i a0, sp, 0
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l32i a2, sp, 0x08
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l32i a3, sp, 0x0c
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l32i a4, sp, 0x10
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rsr.excsave1 a1 # restore a1 saved by UserExceptionVector
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rfe
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.balign 4
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.LSE_jumptable:
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# The first 5 entries (80 bytes) of this table are unused (registers
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# a0..a4 are handled separately above). Rather than have a whole bunch
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# of wasted space, we just pretend that the table starts 80 bytes
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# earlier in memory.
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.set .LSE_jumptable_base, .LSE_jumptable - (16 * 5)
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.org .LSE_jumptable_base + (16 * 5)
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mov a5, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 6)
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mov a6, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 7)
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mov a7, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 8)
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mov a8, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 9)
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mov a9, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 10)
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mov a10, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 11)
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mov a11, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 12)
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mov a12, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 13)
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mov a13, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 14)
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mov a14, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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.org .LSE_jumptable_base + (16 * 15)
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mov a15, a4
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l32i a2, sp, 0x08
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l32i a4, sp, 0x10
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rsr.excsave1 a1
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rfe
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/* End of LoadStoreErrorHandler */
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.section .bss
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NMIHandlerStack: /* stack space for NMI handler */
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NMIHandlerStack: # stack space for NMI handler
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.skip 4*0x100
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.LNMIHandlerStackTop:
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NMIRegisterSaved: /* register space for saving NMI registers */
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NMIRegisterSaved: # register space for saving NMI registers
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.skip 4*(16 + 6)
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LoadStoreErrorHandlerStack:
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@ -338,6 +38,341 @@ LoadStoreErrorHandlerStack:
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.word 0 # a3
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.word 0 # a4
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/***************************** Exception Vectors *****************************/
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.section .vecbase.text, "x"
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/* Note: Exception vectors must be aligned on a 256-byte (0x100) boundary or
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* they will not function properly. (This is taken care of in the linker
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* script by ensuring .vecbase.text is aligned properly, and putting VecBase
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* right at the beginning of .vecbase.text) */
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.org 0
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VecBase:
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.global VecBase
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/* IMPORTANT: exception vector literals will go here, but we
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* can't have more than 4 otherwise we push DebugExceptionVector past
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* offset 0x10 relative to VecBase. There should be ways to avoid this,
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* and also keep the VecBase offsets easy to read, but this works for
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* now. */
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.literal_position
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.org VecBase + 0x10
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DebugExceptionVector:
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.type DebugExceptionVector, @function
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wsr a0, excsave2
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call0 sdk_user_fatal_exception_handler
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rfi 2
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.org VecBase + 0x20
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NMIExceptionVector:
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.type NMIExceptionVector, @function
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wsr a0, excsave3
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call0 CallNMIExceptionHandler
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rfi 3 # Should never be reached
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.org VecBase + 0x30
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KernelExceptionVector:
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.type KernelExceptionVector, @function
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break 1, 0
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call0 sdk_user_fatal_exception_handler
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rfe
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.org VecBase + 0x50
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UserExceptionVector:
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.type UserExceptionVector, @function
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wsr a1, excsave1
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rsr a1, exccause
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beqi a1, CAUSE_LOADSTORE, LoadStoreErrorHandler
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j UserExceptionHandler
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.org VecBase + 0x70
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DoubleExceptionVector:
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.type DoubleExceptionVector, @function
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break 1, 4
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call0 sdk_user_fatal_exception_handler
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/* Reset vector at offset 0x80 is unused, as vecbase gets reset to mask ROM
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* vectors on chip reset. */
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/*************************** LoadStoreError Handler **************************/
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.section .vecbase.text, "x"
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/* Xtensa "Load/Store Exception" handler:
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* Completes L8/L16 load instructions from Instruction address space, for which
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* the architecture only supports 32-bit reads.
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*
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* Called from UserExceptionVector if EXCCAUSE is LoadStoreErrorCause
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*
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* (Fast path (no branches) is for L8UI)
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*/
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.literal_position
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.balign 4
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LoadStoreErrorHandler:
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.type LoadStoreErrorHandler, @function
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/* Registers are saved in the address corresponding to their register
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* number times 4. This allows a quick and easy mapping later on when
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* needing to store the value to a particular register number. */
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movi sp, LoadStoreErrorHandlerStack
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s32i a0, sp, 0
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s32i a2, sp, 0x08
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s32i a3, sp, 0x0c
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s32i a4, sp, 0x10
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rsr a0, sar # Save SAR in a0 to restore later
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/* Examine the opcode which generated the exception */
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/* Note: Instructions are in this order to avoid pipeline stalls. */
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rsr a2, epc1
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movi a3, ~3
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ssa8l a2 # sar is now correct shift for aligned read
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and a2, a2, a3 # a2 now 4-byte aligned address of instruction
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l32i a4, a2, 0
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l32i a2, a2, 4
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movi a3, 0x00700F # opcode mask for l8ui/l16si/l16ui
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src a2, a2, a4 # a2 now instruction that failed
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and a3, a2, a3 # a3 is masked instruction
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bnei a3, 0x000002, .LSE_check_l16
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/* Note: At this point, opcode could technically be one of two things:
|
||||
* xx0xx2 (L8UI)
|
||||
* xx8xx2 (Reserved (invalid) opcode)
|
||||
* It is assumed that we'll never get to this point from an illegal
|
||||
* opcode, so we don't bother to check for that case and presume this
|
||||
* is always an L8UI. */
|
||||
|
||||
movi a4, ~3
|
||||
rsr a3, excvaddr # read faulting address
|
||||
and a4, a3, a4 # a4 now word aligned read address
|
||||
|
||||
l32i a4, a4, 0 # perform the actual read
|
||||
ssa8l a3 # sar is now shift to extract a3's byte
|
||||
srl a3, a4 # shift right correct distance
|
||||
extui a4, a3, 0, 8 # mask off bits we need for an l8
|
||||
|
||||
.LSE_post_fetch:
|
||||
/* We jump back here after either the L8UI or the L16*I routines do the
|
||||
* necessary work to read the value from memory.
|
||||
* At this point, a2 holds the faulting instruction and a4 holds the
|
||||
* correctly read value.
|
||||
|
||||
* Restore original SAR value (saved in a0) and update EPC so we'll
|
||||
* return back to the instruction following the one we just emulated */
|
||||
|
||||
/* Note: Instructions are in this order to avoid pipeline stalls */
|
||||
rsr a3, epc1
|
||||
wsr a0, sar
|
||||
addi a3, a3, 0x3
|
||||
wsr a3, epc1
|
||||
|
||||
/* Stupid opcode tricks: The jumptable we use later on needs 16 bytes
|
||||
* per entry (so we can avoid a second jump by just doing a RFE inside
|
||||
* each entry). Unfortunately, however, Xtensa doesn't have an addx16
|
||||
* operation to make that easy for us. Luckily, all of the faulting
|
||||
* opcodes we're processing are guaranteed to have bit 3 be zero, which
|
||||
* means if we just shift the register bits of the opcode down by 3
|
||||
* instead of 4, we will get the register number multiplied by 2. This
|
||||
* combined with an addx8 will give us an effective addx16 without
|
||||
* needing any extra shift operations. */
|
||||
extui a2, a2, 3, 5 # a2 is now destination register 0-15 times 2
|
||||
|
||||
bgei a2, 10, .LSE_assign_reg # a5..a15 use jumptable
|
||||
beqi a2, 2, .LSE_assign_a1 # a1 uses a special routine
|
||||
|
||||
/* We're storing into a0 or a2..a4, which are all saved in our "stack"
|
||||
* area. Calculate the correct address and stick the value in there,
|
||||
* then just do our normal restore and RFE (no jumps required, which
|
||||
* actually makes a0..a4 substantially faster). */
|
||||
addx2 a2, a2, sp
|
||||
s32i a4, a2, 0
|
||||
|
||||
/* Restore all regs and return */
|
||||
l32i a0, sp, 0
|
||||
l32i a2, sp, 0x08
|
||||
l32i a3, sp, 0x0c
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1 # restore a1 saved by UserExceptionVector
|
||||
rfe
|
||||
|
||||
.LSE_assign_reg:
|
||||
/* At this point, a2 contains the register number times 2, a4 is the
|
||||
* read value. */
|
||||
|
||||
/* Calculate the jumptable address, and restore all regs except a2 and
|
||||
* a4 so we have less to do after jumping. */
|
||||
/* Note: Instructions are in this order to avoid pipeline stalls. */
|
||||
movi a3, .LSE_jumptable_base
|
||||
l32i a0, sp, 0
|
||||
addx8 a2, a2, a3 # a2 is now the address to jump to
|
||||
l32i a3, sp, 0x0c
|
||||
|
||||
jx a2
|
||||
|
||||
.balign 4
|
||||
.LSE_check_l16:
|
||||
/* At this point, a2 contains the opcode, a3 is masked opcode */
|
||||
movi a4, 0x001002 # l16si or l16ui opcode after masking
|
||||
bne a3, a4, .LSE_wrong_opcode
|
||||
|
||||
/* Note: At this point, the opcode could be one of two things:
|
||||
* xx1xx2 (L16UI)
|
||||
* xx9xx2 (L16SI)
|
||||
* Both of these we can handle. */
|
||||
|
||||
movi a4, ~3
|
||||
rsr a3, excvaddr # read faulting address
|
||||
and a4, a3, a4 # a4 now word aligned read address
|
||||
|
||||
l32i a4, a4, 0 # perform the actual read
|
||||
ssa8l a3 # sar is now shift to extract a3's bytes
|
||||
srl a3, a4 # shift right correct distance
|
||||
extui a4, a3, 0, 16 # mask off bits we need for an l16
|
||||
|
||||
bbci a2, 15, .LSE_post_fetch # Not a signed op
|
||||
bbci a4, 15, .LSE_post_fetch # Value does not need sign-extension
|
||||
|
||||
movi a3, 0xFFFF0000
|
||||
or a4, a3, a4 # set 32-bit sign bits
|
||||
j .LSE_post_fetch
|
||||
|
||||
.LSE_wrong_opcode:
|
||||
/* If we got here it's not an opcode we can try to fix, so bomb out.
|
||||
* Restore registers so any dump the fatal exception routine produces
|
||||
* will have correct values */
|
||||
wsr a0, sar
|
||||
l32i a0, sp, 0
|
||||
l32i a2, sp, 0x08
|
||||
l32i a3, sp, 0x0c
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
call0 sdk_user_fatal_exception_handler
|
||||
|
||||
.balign 4
|
||||
.LSE_assign_a1:
|
||||
/* a1 is saved in excsave1, so just update that with the value, */
|
||||
wsr a4, excsave1
|
||||
/* Then restore all regs and return */
|
||||
l32i a0, sp, 0
|
||||
l32i a2, sp, 0x08
|
||||
l32i a3, sp, 0x0c
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.balign 4
|
||||
.LSE_jumptable:
|
||||
/* The first 5 entries (80 bytes) of this table are unused (registers
|
||||
* a0..a4 are handled separately above). Rather than have a whole bunch
|
||||
* of wasted space, we just pretend that the table starts 80 bytes
|
||||
* earlier in memory. */
|
||||
.set .LSE_jumptable_base, .LSE_jumptable - (16 * 5)
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 5)
|
||||
mov a5, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 6)
|
||||
mov a6, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 7)
|
||||
mov a7, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 8)
|
||||
mov a8, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 9)
|
||||
mov a9, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 10)
|
||||
mov a10, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 11)
|
||||
mov a11, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 12)
|
||||
mov a12, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 13)
|
||||
mov a13, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 14)
|
||||
mov a14, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
.org .LSE_jumptable_base + (16 * 15)
|
||||
mov a15, a4
|
||||
l32i a2, sp, 0x08
|
||||
l32i a4, sp, 0x10
|
||||
rsr a1, excsave1
|
||||
rfe
|
||||
|
||||
/****************************** call_user_start ******************************/
|
||||
|
||||
.section .vecbase.text, "x"
|
||||
|
||||
/* This is the first entrypoint called from the ROM after loading the image
|
||||
* into IRAM. It just sets up the VECBASE register to point at our own
|
||||
* exception vectors and then calls sdk_user_start() */
|
||||
|
||||
.literal_position
|
||||
|
||||
.balign 4
|
||||
call_user_start:
|
||||
.global call_user_start
|
||||
.type call_user_start, @function
|
||||
|
||||
movi a2, VecBase
|
||||
wsr a2, vecbase
|
||||
call0 sdk_user_start
|
||||
|
||||
/*************************** NMI Exception Handler ***************************/
|
||||
|
||||
.section .vecbase.text, "x"
|
||||
|
||||
/* Save register relative to a0 */
|
||||
.macro SAVE_REG register, regnum
|
||||
s32i \register, a0, (4 * (\regnum + 6))
|
||||
|
|
@ -348,35 +383,26 @@ LoadStoreErrorHandlerStack:
|
|||
l32i \register, sp, (4 * (\regnum + 6))
|
||||
.endm
|
||||
|
||||
.text
|
||||
.section .vecbase.text
|
||||
.literal_position
|
||||
.align 4
|
||||
.global call_user_start
|
||||
.type call_user_start, @function
|
||||
call_user_start:
|
||||
movi a2, VecBase
|
||||
wsr.vecbase a2
|
||||
call0 sdk_user_start
|
||||
|
||||
.literal_position
|
||||
.align 16
|
||||
.type CallNMIExceptionHandler, @function
|
||||
.balign 16
|
||||
CallNMIExceptionHandler:
|
||||
.type CallNMIExceptionHandler, @function
|
||||
|
||||
movi a0, NMIRegisterSaved
|
||||
SAVE_REG a2, 2
|
||||
SAVE_REG sp, 1
|
||||
SAVE_REG a3, 3
|
||||
rsr.excsave3 a2 /* a2 is now former a0 */
|
||||
rsr a2, excsave3 # a2 is now former a0
|
||||
SAVE_REG a4, 4
|
||||
SAVE_REG a2, 0
|
||||
rsr.epc1 a3
|
||||
rsr.exccause a4
|
||||
rsr a3, epc1
|
||||
rsr a4, exccause
|
||||
SAVE_REG a3, -5
|
||||
SAVE_REG a4, -4
|
||||
rsr.excvaddr a3
|
||||
rsr a3, excvaddr
|
||||
SAVE_REG a3, -3
|
||||
rsr.excsave1 a3
|
||||
rsr a3, excsave1
|
||||
SAVE_REG a3, -2
|
||||
SAVE_REG a5, 5
|
||||
SAVE_REG a6, 6
|
||||
|
|
@ -391,16 +417,16 @@ CallNMIExceptionHandler:
|
|||
SAVE_REG a15, 15
|
||||
movi sp, .LNMIHandlerStackTop
|
||||
movi a0, 0
|
||||
movi a2, 0x23 /* argument for handler */
|
||||
wsr.ps a2
|
||||
movi a2, 0x23 # argument for handler
|
||||
wsr a2, ps
|
||||
rsync
|
||||
rsr.sar a14
|
||||
s32i a14, sp, 0 /* this is also NMIRegisterSaved+0 */
|
||||
rsr a14, sar
|
||||
s32i a14, sp, 0 # this is also NMIRegisterSaved+0
|
||||
call0 sdk_wDev_ProcessFiq
|
||||
l32i a15, sp, 0
|
||||
wsr.sar a15
|
||||
wsr a15, sar
|
||||
movi a2, 0x33
|
||||
wsr.ps a2
|
||||
wsr a2, ps
|
||||
rsync
|
||||
LOAD_REG a4, 4
|
||||
LOAD_REG a5, 5
|
||||
|
|
@ -416,85 +442,98 @@ CallNMIExceptionHandler:
|
|||
LOAD_REG a15, 15
|
||||
LOAD_REG a2, -5
|
||||
LOAD_REG a3, -4
|
||||
wsr.epc1 a2
|
||||
wsr.exccause a3
|
||||
wsr a2, epc1
|
||||
wsr a3, exccause
|
||||
LOAD_REG a2, -3
|
||||
LOAD_REG a3, -2
|
||||
wsr.excvaddr a2
|
||||
wsr.excsave1 a3
|
||||
wsr a2, excvaddr
|
||||
wsr a3, excsave1
|
||||
LOAD_REG a0, 0
|
||||
/* set dport nmi status bit 0 (wDev_ProcessFiq clears & verifies this bit stays cleared,
|
||||
see http://esp8266-re.foogod.com/wiki/WDev_ProcessFiq_%28IoT_RTOS_SDK_0.9.9%29) */
|
||||
/* set dport nmi status bit 0 (wDev_ProcessFiq clears & verifies this
|
||||
* bit stays cleared, see
|
||||
* http://esp8266-re.foogod.com/wiki/WDev_ProcessFiq_%28IoT_RTOS_SDK_0.9.9%29)
|
||||
*/
|
||||
movi a2, 0x3ff00000
|
||||
movi a3, 0x1
|
||||
s32i a3, a2, 0
|
||||
LOAD_REG a2, 2
|
||||
LOAD_REG a3, 3
|
||||
LOAD_REG a1, 1
|
||||
rfi 0x3
|
||||
rfi 3
|
||||
|
||||
.type UserExceptionHandler, @function
|
||||
/*********************** General UserException Handler ***********************/
|
||||
|
||||
.section .vecbase.text, "x"
|
||||
|
||||
/* Called by UserExceptionVector if EXCCAUSE is anything other than
|
||||
* LoadStoreCause. */
|
||||
|
||||
.literal_position
|
||||
|
||||
.balign 4
|
||||
UserExceptionHandler:
|
||||
xsr.excsave1 a0 # a0 now contains sp
|
||||
.type UserExceptionHandler, @function
|
||||
xsr a0, excsave1 # a0 now contains sp
|
||||
mov sp, a0
|
||||
addi sp, sp, -0x50
|
||||
s32i a0, sp, 0x10
|
||||
rsr.ps a0
|
||||
rsr a0, ps
|
||||
s32i a0, sp, 0x08
|
||||
rsr.epc1 a0
|
||||
rsr a0, epc1
|
||||
s32i a0, sp, 0x04
|
||||
rsr.excsave1 a0
|
||||
rsr a0, excsave1
|
||||
s32i a0, sp, 0x0c
|
||||
movi a0, _xt_user_exit
|
||||
s32i a0, sp, 0x0
|
||||
call0 sdk__xt_int_enter
|
||||
movi a0, 0x23
|
||||
wsr.ps a0
|
||||
wsr a0, ps
|
||||
rsync
|
||||
rsr.exccause a2
|
||||
rsr a2, exccause
|
||||
beqi a2, CAUSE_LVL1INT, UserHandleInterrupt
|
||||
/* Any UserException cause other than level 1 interrupt triggers a panic */
|
||||
/* Any UserException cause other than level 1 interrupt should panic */
|
||||
UserFailOtherExceptionCause:
|
||||
break 1, 1
|
||||
call0 sdk_user_fatal_exception_handler
|
||||
UserHandleInterrupt:
|
||||
rsil a0, 1
|
||||
rsr.intenable a2
|
||||
rsr.interrupt a3
|
||||
rsr a2, intenable
|
||||
rsr a3, interrupt
|
||||
movi a4, 0x3fff
|
||||
and a2, a2, a3
|
||||
and a2, a2, a4 /* a2 = 0x3FFF & INTENABLE & INTERRUPT */
|
||||
and a2, a2, a4 # a2 = 0x3FFF & INTENABLE & INTERRUPT
|
||||
UserHandleTimer:
|
||||
movi a3, 0xffbf
|
||||
and a3, a2, a3 /* a3 = a2 & 0xFFBF, ie remove 0x40 from a2 if set */
|
||||
bnez a3, UserTimerDone /* bits other than 0x40 are set */
|
||||
and a3, a2, a3 # a3 = a2 with bit 6 cleared
|
||||
bnez a3, UserTimerDone # If any non-timer interrupt bits set
|
||||
movi a3, 0x40
|
||||
sub a12, a2, a3 /* a12 = a2 - 0x40 -- Will be zero if bit 6 set */
|
||||
call0 sdk__xt_timer_int /* tick timer interrupt */
|
||||
mov a2, a12 /* restore a2 from a12, ie zero */
|
||||
sub a12, a2, a3 # a12 = a2 - 0x40 -- Will be zero if bit 6 set
|
||||
call0 sdk__xt_timer_int # tick timer interrupt
|
||||
mov a2, a12 # restore a2 from a12, ie zero
|
||||
beqz a2, UserIntDone
|
||||
UserTimerDone:
|
||||
call0 _xt_isr_handler
|
||||
bnez a2, UserHandleTimer
|
||||
UserIntDone:
|
||||
beqz a2, UserIntExit
|
||||
break 1, 1 /* non-zero remnant in a2 means fail */
|
||||
/* FIXME: this code will never be reached */
|
||||
break 1, 1
|
||||
call0 sdk_user_fatal_exception_handler
|
||||
UserIntExit:
|
||||
call0 sdk__xt_int_exit /* jumps to _xt_user_exit. Never returns here */
|
||||
call0 sdk__xt_int_exit # jumps to _xt_user_exit. Never returns here
|
||||
|
||||
/* _xt_user_exit is used to exit interrupt context.
|
||||
TODO: Find a better place for this to live.
|
||||
*/
|
||||
.text
|
||||
.section .text
|
||||
|
||||
/* _xt_user_exit is used to exit interrupt context. */
|
||||
/* TODO: Find a better place for this to live. */
|
||||
_xt_user_exit:
|
||||
.global _xt_user_exit
|
||||
.type _xt_user_exit, @function
|
||||
_xt_user_exit:
|
||||
|
||||
l32i a0, sp, 0x8
|
||||
wsr.ps a0
|
||||
wsr a0, ps
|
||||
l32i a0, sp, 0x4
|
||||
wsr.epc1 a0
|
||||
wsr a0, epc1
|
||||
l32i a0, sp, 0xc
|
||||
l32i sp, sp, 0x10
|
||||
rsync
|
||||
|
|
|
|||
Loading…
Reference in a new issue