diff options
Diffstat (limited to 'ports/risc-v32/gnu/src/tx_thread_stack_build.S')
| -rw-r--r-- | ports/risc-v32/gnu/src/tx_thread_stack_build.S | 104 |
1 files changed, 27 insertions, 77 deletions
diff --git a/ports/risc-v32/gnu/src/tx_thread_stack_build.S b/ports/risc-v32/gnu/src/tx_thread_stack_build.S index 4ade60ca..3f7ae5d6 100644 --- a/ports/risc-v32/gnu/src/tx_thread_stack_build.S +++ b/ports/risc-v32/gnu/src/tx_thread_stack_build.S @@ -21,6 +21,10 @@ .section .text + +#include "tx_port.h" + .equ TX_TRAP_FRAME_SIZE, TX_RISCV_TRAP_FRAME_SIZE + /**************************************************************************/ /* */ /* FUNCTION RELEASE */ @@ -92,42 +96,14 @@ _tx_thread_stack_build: x11 26 Initial a1 x10 27 Initial a0 x1 28 Initial ra - -- 29 reserved + mstatus 29 Initial mstatus seed mepc 30 Initial mepc -If floating point support: - f0 31 Initial ft0 - f1 32 Initial ft1 - f2 33 Initial ft2 - f3 34 Initial ft3 - f4 35 Initial ft4 - f5 36 Initial ft5 - f6 37 Initial ft6 - f7 38 Initial ft7 - f8 39 Initial fs0 - f9 40 Initial fs1 - f10 41 Initial fa0 - f11 42 Initial fa1 - f12 43 Initial fa2 - f13 44 Initial fa3 - f14 45 Initial fa4 - f15 46 Initial fa5 - f16 47 Initial fa6 - f17 48 Initial fa7 - f18 49 Initial fs2 - f19 50 Initial fs3 - f20 51 Initial fs4 - f21 52 Initial fs5 - f22 53 Initial fs6 - f23 54 Initial fs7 - f24 55 Initial fs8 - f25 56 Initial fs9 - f26 57 Initial fs10 - f27 58 Initial fs11 - f28 59 Initial ft8 - f29 60 Initial ft9 - f30 61 Initial ft10 - f31 62 Initial ft11 - fscr 63 Initial fscr + -- 31 pad (0) + If floating point support (double ABI), byte offsets from + the frame base: + f0-f31 128 + i*8 Initial FP registers (all 0) + fcsr 384 Initial fcsr (0) + pad 388-399 (0) Stack Bottom: (higher memory address) */ @@ -137,11 +113,7 @@ If floating point support: /* Actually build the stack frame. */ -#if defined(__riscv_float_abi_single) || defined(__riscv_float_abi_double) - addi t0, t0, -65*4 -#else - addi t0, t0, -32*4 // Allocate space for the stack frame -#endif + addi t0, t0, -TX_TRAP_FRAME_SIZE // Allocate space for the stack frame li t1, 1 // Build stack type sw t1, 0*4(t0) // Place stack type on the top sw zero, 1*4(t0) // Initial s11 @@ -173,44 +145,22 @@ If floating point support: sw zero, 27*4(t0) // Initial a0 sw zero, 28*4(t0) // Initial ra sw a1, 30*4(t0) // Initial mepc (thread entry point) -#if defined(__riscv_float_abi_single) || defined(__riscv_float_abi_double) - sw zero, 31*4(t0) // Initial ft0 - sw zero, 32*4(t0) // Initial ft1 - sw zero, 33*4(t0) // Initial ft2 - sw zero, 34*4(t0) // Initial ft3 - sw zero, 35*4(t0) // Initial ft4 - sw zero, 36*4(t0) // Initial ft5 - sw zero, 37*4(t0) // Initial ft6 - sw zero, 38*4(t0) // Initial ft7 - sw zero, 39*4(t0) // Initial fs0 - sw zero, 40*4(t0) // Initial fs1 - sw zero, 41*4(t0) // Initial fa0 - sw zero, 42*4(t0) // Initial fa1 - sw zero, 43*4(t0) // Initial fa2 - sw zero, 44*4(t0) // Initial fa3 - sw zero, 45*4(t0) // Initial fa4 - sw zero, 46*4(t0) // Initial fa5 - sw zero, 47*4(t0) // Initial fa6 - sw zero, 48*4(t0) // Initial fa7 - sw zero, 49*4(t0) // Initial fs2 - sw zero, 50*4(t0) // Initial fs3 - sw zero, 51*4(t0) // Initial fs4 - sw zero, 52*4(t0) // Initial fs5 - sw zero, 53*4(t0) // Initial fs6 - sw zero, 54*4(t0) // Initial fs7 - sw zero, 55*4(t0) // Initial fs8 - sw zero, 56*4(t0) // Initial fs9 - sw zero, 57*4(t0) // Initial fs10 - sw zero, 58*4(t0) // Initial fs11 - sw zero, 59*4(t0) // Initial ft8 - sw zero, 60*4(t0) // Initial ft9 - sw zero, 61*4(t0) // Initial ft10 - sw zero, 62*4(t0) // Initial ft11 - csrr a1, fcsr // Read fcsr for initial value - sw a1, 63*4(t0) // Initial fcsr - sw zero, 64*4(t0) // Reserved word (0) + sw zero, 31*4(t0) // Pad word (0) +#if defined(__riscv_float_abi_double) + li t1, 0x6000 // mstatus seed: FS = Dirty (bits 14:13 = 11) + sw t1, 29*4(t0) // so the first dispatch restores the clean FP state + + /* Zero the whole FP area: f0-f31 double slots (128-383), fcsr (384) + and the pad words up to the frame end. Threads start with clean + FP registers and fcsr = 0. */ + addi t1, t0, 32*4 // First FP-area word (offset 128) + addi t2, t0, TX_TRAP_FRAME_SIZE // One past the frame end (offset 400) +_tx_thread_stack_build_fp_zero: + sw zero, 0(t1) // Clear FP-area word + addi t1, t1, 4 + bne t1, t2, _tx_thread_stack_build_fp_zero #else - sw zero, 31*4(t0) // Reserved word (0) + sw zero, 29*4(t0) // Initial mstatus slot (0, no FP gate) #endif /* Setup stack pointer. */ |