diff options
Diffstat (limited to 'arch/powerpc/platforms/cell/spufs/spu_save.c')
| -rw-r--r-- | arch/powerpc/platforms/cell/spufs/spu_save.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/cell/spufs/spu_save.c b/arch/powerpc/platforms/cell/spufs/spu_save.c new file mode 100644 index 000000000..28c88e324 --- /dev/null +++ b/arch/powerpc/platforms/cell/spufs/spu_save.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * spu_save.c + * + * (C) Copyright IBM Corp. 2005 + * + * SPU-side context save sequence outlined in + * Synergistic Processor Element Book IV + * + * Author: Mark Nutter <mnutter@us.ibm.com> + */ + + +#ifndef LS_SIZE +#define LS_SIZE 0x40000 /* 256K (in bytes) */ +#endif + +typedef unsigned int u32; +typedef unsigned long long u64; + +#include <spu_intrinsics.h> +#include <asm/spu_csa.h> +#include "spu_utils.h" + +static inline void save_event_mask(void) +{ + unsigned int offset; + + /* Save, Step 2: + * Read the SPU_RdEventMsk channel and save to the LSCSA. + */ + offset = LSCSA_QW_OFFSET(event_mask); + regs_spill[offset].slot[0] = spu_readch(SPU_RdEventMask); +} + +static inline void save_tag_mask(void) +{ + unsigned int offset; + + /* Save, Step 3: + * Read the SPU_RdTagMsk channel and save to the LSCSA. + */ + offset = LSCSA_QW_OFFSET(tag_mask); + regs_spill[offset].slot[0] = spu_readch(MFC_RdTagMask); +} + +static inline void save_upper_240kb(addr64 lscsa_ea) +{ + unsigned int ls = 16384; + unsigned int list = (unsigned int)&dma_list[0]; + unsigned int size = sizeof(dma_list); + unsigned int tag_id = 0; + unsigned int cmd = 0x24; /* PUTL */ + + /* Save, Step 7: + * Enqueue the PUTL command (tag 0) to the MFC SPU command + * queue to transfer the remaining 240 kb of LS to CSA. + */ + spu_writech(MFC_LSA, ls); + spu_writech(MFC_EAH, lscsa_ea.ui[0]); + spu_writech(MFC_EAL, list); + spu_writech(MFC_Size, size); + spu_writech(MFC_TagID, tag_id); + spu_writech(MFC_Cmd, cmd); +} + +static inline void save_fpcr(void) +{ + // vector unsigned int fpcr; + unsigned int offset; + + /* Save, Step 9: + * Issue the floating-point status and control register + * read instruction, and save to the LSCSA. + */ + offset = LSCSA_QW_OFFSET(fpcr); + regs_spill[offset].v = spu_mffpscr(); +} + +static inline void save_decr(void) +{ + unsigned int offset; + + /* Save, Step 10: + * Read and save the SPU_RdDec channel data to + * the LSCSA. + */ + offset = LSCSA_QW_OFFSET(decr); + regs_spill[offset].slot[0] = spu_readch(SPU_RdDec); +} + +static inline void save_srr0(void) +{ + unsigned int offset; + + /* Save, Step 11: + * Read and save the SPU_WSRR0 channel data to + * the LSCSA. + */ + offset = LSCSA_QW_OFFSET(srr0); + regs_spill[offset].slot[0] = spu_readch(SPU_RdSRR0); +} + +static inline void spill_regs_to_mem(addr64 lscsa_ea) +{ + unsigned int ls = (unsigned int)®s_spill[0]; + unsigned int size = sizeof(regs_spill); + unsigned int tag_id = 0; + unsigned int cmd = 0x20; /* PUT */ + + /* Save, Step 13: + * Enqueue a PUT command (tag 0) to send the LSCSA + * to the CSA. + */ + spu_writech(MFC_LSA, ls); + spu_writech(MFC_EAH, lscsa_ea.ui[0]); + spu_writech(MFC_EAL, lscsa_ea.ui[1]); + spu_writech(MFC_Size, size); + spu_writech(MFC_TagID, tag_id); + spu_writech(MFC_Cmd, cmd); +} + +static inline void enqueue_sync(addr64 lscsa_ea) +{ + unsigned int tag_id = 0; + unsigned int cmd = 0xCC; + + /* Save, Step 14: + * Enqueue an MFC_SYNC command (tag 0). + */ + spu_writech(MFC_TagID, tag_id); + spu_writech(MFC_Cmd, cmd); +} + +static inline void save_complete(void) +{ + /* Save, Step 18: + * Issue a stop-and-signal instruction indicating + * "save complete". Note: This function will not + * return!! + */ + spu_stop(SPU_SAVE_COMPLETE); +} + +/** + * main - entry point for SPU-side context save. + * + * This code deviates from the documented sequence as follows: + * + * 1. The EA for LSCSA is passed from PPE in the + * signal notification channels. + * 2. All 128 registers are saved by crt0.o. + */ +int main() +{ + addr64 lscsa_ea; + + lscsa_ea.ui[0] = spu_readch(SPU_RdSigNotify1); + lscsa_ea.ui[1] = spu_readch(SPU_RdSigNotify2); + + /* Step 1: done by exit(). */ + save_event_mask(); /* Step 2. */ + save_tag_mask(); /* Step 3. */ + set_event_mask(); /* Step 4. */ + set_tag_mask(); /* Step 5. */ + build_dma_list(lscsa_ea); /* Step 6. */ + save_upper_240kb(lscsa_ea); /* Step 7. */ + /* Step 8: done by exit(). */ + save_fpcr(); /* Step 9. */ + save_decr(); /* Step 10. */ + save_srr0(); /* Step 11. */ + enqueue_putllc(lscsa_ea); /* Step 12. */ + spill_regs_to_mem(lscsa_ea); /* Step 13. */ + enqueue_sync(lscsa_ea); /* Step 14. */ + set_tag_update(); /* Step 15. */ + read_tag_status(); /* Step 16. */ + read_llar_status(); /* Step 17. */ + save_complete(); /* Step 18. */ + + return 0; +} |