linux/arch/powerpc/platforms/cell/spufs/spu_save.c

196 lines
4.9 KiB
C

/*
* 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>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#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_RdEventStatMask);
}
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)&regs_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;
}