Commit 3860d52f authored by Lu Feifei's avatar Lu Feifei Committed by guzitao
Browse files

sw64: add SIMD emulation for guest IO access 

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I56WV8



--------------------------------

To support SIMD IO access in guest, an exception type IF_SIMDEMU has
been added in do_entIF(), which is used to emualte SIMD load/store.

Currently, only vldd and vstd are supported for emulation.

Signed-off-by: default avatarLu Feifei <lufeifei@wxiat.com>
Reviewed-by: default avatarHe Sheng <hesheng@wxiat.com>
Signed-off-by: default avatarGu Zitao <guzitao@wxiat.com>
parent 7cf73995

arch/sw_64/kernel/entry.S

+1 −1
Original line number Diff line number Diff line
@@ -121,7 +121,7 @@ entMM: 
entIF:

	SAVE_ALL

	ldi	$26, ret_from_sys_call

	mov	$sp, $17

	mov	$sp, $18

	call	$31, do_entIF

	.end entIF

arch/sw_64/kernel/traps.c

+27 −1
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ enum SW64_IF_TYPES { 
	IF_GENTRAP,

	IF_FEN,

	IF_OPDEC,

	IF_SIMDEMU,

};



void show_regs(struct pt_regs *regs)
@@ -165,12 +166,32 @@ do_entArith(unsigned long summary, unsigned long write_mask, 
	force_sig_fault(SIGFPE, si_code, (void __user *)regs->pc, 0);

}



void simd_emulate(unsigned int inst, unsigned long va)

{

	unsigned long *fp;

	int instr_opc, reg;



	instr_opc = (inst >> 26) & 0x3f;

	reg = (inst >> 21) & 0x1f;

	fp = (unsigned long *) va;



	switch (instr_opc) {

	case 0x0d: /* vldd */

		sw64_write_simd_fp_reg_d(reg, fp[0], fp[1], fp[2], fp[3]);

		return;



	case 0x0f: /* vstd */

		sw64_read_simd_fp_m_d(reg, fp);

		return;

	}

}



/*

 * BPT/GENTRAP/OPDEC make regs->pc = exc_pc + 4. debugger should

 * do something necessary to handle it correctly.

 */

asmlinkage void

do_entIF(unsigned long inst_type, struct pt_regs *regs)

do_entIF(unsigned long inst_type, unsigned long va, struct pt_regs *regs)

{

	int signo, code;

	unsigned int inst, type;
@@ -178,6 +199,11 @@ do_entIF(unsigned long inst_type, struct pt_regs *regs) 
	type = inst_type & 0xffffffff;

	inst = inst_type >> 32;



	if (type == IF_SIMDEMU) {

		simd_emulate(inst, va);

		return;

	}



	if (!user_mode(regs) && type != IF_OPDEC) {

		if (type == IF_BREAKPOINT) {

			/* support kgdb */