From: Miodrag Dinic <miodrag.di...@imgtec.com>
Add handling of missaligned access for DSP load instructions
lwx & lhx.
Since DSP instructions share SPECIAL3 opcode with other non-DSP
instructions, necessary logic was inserted for distinguishing
between instructions with SPECIAL3 opcode. For that purpose,
the instruction format for DSP instructions is added to
arch/mips/include/uapi/asm/inst.h.
Signed-off-by: Miodrag Dinic <miodrag.di...@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.marko...@imgtech.com>
---
arch/mips/include/uapi/asm/inst.h | 11 +++
arch/mips/kernel/unaligned.c | 174 ++++++++++++++++++++++----------------
2 files changed, 111 insertions(+), 74 deletions(-)
diff --git a/arch/mips/include/uapi/asm/inst.h
b/arch/mips/include/uapi/asm/inst.h
index b5e46ae..302ad9a 100644
--- a/arch/mips/include/uapi/asm/inst.h
+++ b/arch/mips/include/uapi/asm/inst.h
@@ -755,6 +755,16 @@ struct msa_mi10_format { /* MSA MI10 */
;))))))
};
+struct dsp_format { /* SPEC3 DSP format instructions */
+ __BITFIELD_FIELD(unsigned int opcode : 6,
+ __BITFIELD_FIELD(unsigned int base : 5,
+ __BITFIELD_FIELD(unsigned int index : 5,
+ __BITFIELD_FIELD(unsigned int rd : 5,
+ __BITFIELD_FIELD(unsigned int op : 5,
+ __BITFIELD_FIELD(unsigned int func : 6,
+ ;))))))
+};
+
struct spec3_format { /* SPEC3 */
__BITFIELD_FIELD(unsigned int opcode:6,
__BITFIELD_FIELD(unsigned int rs:5,
@@ -1046,6 +1056,7 @@ union mips_instruction {
struct b_format b_format;
struct ps_format ps_format;
struct v_format v_format;
+ struct dsp_format dsp_format;
struct spec3_format spec3_format;
struct fb_format fb_format;
struct fp0_format fp0_format;
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index f806ee5..67946bb 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -939,88 +939,114 @@ static void emulate_load_store_insn(struct pt_regs *regs,
* The remaining opcodes are the ones that are really of
* interest.
*/
-#ifdef CONFIG_EVA
case spec3_op:
- /*
- * we can land here only from kernel accessing user memory,
- * so we need to "switch" the address limit to user space, so
- * address check can work properly.
- */
- seg = get_fs();
- set_fs(USER_DS);
- switch (insn.spec3_format.func) {
- case lhe_op:
- if (!access_ok(VERIFY_READ, addr, 2)) {
- set_fs(seg);
- goto sigbus;
- }
- LoadHWE(addr, value, res);
- if (res) {
- set_fs(seg);
- goto fault;
- }
- compute_return_epc(regs);
- regs->regs[insn.spec3_format.rt] = value;
- break;
- case lwe_op:
- if (!access_ok(VERIFY_READ, addr, 4)) {
- set_fs(seg);
- goto sigbus;
+ if (insn.dsp_format.func == lx_op) {
+ switch (insn.dsp_format.op) {
+ case lwx_op:
+ if (!access_ok(VERIFY_READ, addr, 4))
+ goto sigbus;
+ LoadW(addr, value, res);
+ if (res)
+ goto fault;
+ compute_return_epc(regs);
+ regs->regs[insn.dsp_format.rd] = value;
+ break;
+ case lhx_op:
+ if (!access_ok(VERIFY_READ, addr, 2))
+ goto sigbus;
+ LoadHW(addr, value, res);
+ if (res)
+ goto fault;
+ compute_return_epc(regs);
+ regs->regs[insn.dsp_format.rd] = value;
+ break;
+ default:
+ goto sigill;
}
+ }
+#ifdef CONFIG_EVA
+ else {
+ /*
+ * we can land here only from kernel accessing user
+ * memory, so we need to "switch" the address limit to
+ * user space, so that address check can work properly.
+ */
+ seg = get_fs();
+ set_fs(USER_DS);
+ switch (insn.spec3_format.func) {
+ case lhe_op:
+ if (!access_ok(VERIFY_READ, addr, 2)) {
+ set_fs(seg);
+ goto sigbus;
+ }
+ LoadHWE(addr, value, res);
+ if (res) {
+ set_fs(seg);
+ goto fault;
+ }
+ compute_return_epc(regs);
+ regs->regs[insn.spec3_format.rt] = value;
+ break;
+ case lwe_op:
+ if (!access_ok(VERIFY_READ, addr, 4)) {
+ set_fs(seg);
+ goto sigbus;
+ }
LoadWE(addr, value, res);
- if (res) {
- set_fs(seg);
- goto fault;
- }
- compute_return_epc(regs);
- regs->regs[insn.spec3_format.rt] = value;
- break;
- case lhue_op:
- if (!access_ok(VERIFY_READ, addr, 2)) {
- set_fs(seg);
- goto sigbus;
- }
- LoadHWUE(addr, value, res);
- if (res) {
- set_fs(seg);
- goto fault;
- }
- compute_return_epc(regs);
- regs->regs[insn.spec3_format.rt] = value;
- break;
- case she_op:
- if (!access_ok(VERIFY_WRITE, addr, 2)) {
- set_fs(seg);
- goto sigbus;
- }
- compute_return_epc(regs);
- value = regs->regs[insn.spec3_format.rt];
- StoreHWE(addr, value, res);
- if (res) {
- set_fs(seg);
- goto fault;
- }
- break;
- case swe_op:
- if (!access_ok(VERIFY_WRITE, addr, 4)) {
- set_fs(seg);
- goto sigbus;
- }
- compute_return_epc(regs);
- value = regs->regs[insn.spec3_format.rt];
- StoreWE(addr, value, res);
- if (res) {
+ if (res) {
+ set_fs(seg);
+ goto fault;
+ }
+ compute_return_epc(regs);
+ regs->regs[insn.spec3_format.rt] = value;
+ break;
+ case lhue_op:
+ if (!access_ok(VERIFY_READ, addr, 2)) {
+ set_fs(seg);
+ goto sigbus;
+ }
+ LoadHWUE(addr, value, res);
+ if (res) {
+ set_fs(seg);
+ goto fault;
+ }
+ compute_return_epc(regs);
+ regs->regs[insn.spec3_format.rt] = value;
+ break;
+ case she_op:
+ if (!access_ok(VERIFY_WRITE, addr, 2)) {
+ set_fs(seg);
+ goto sigbus;
+ }
+ compute_return_epc(regs);
+ value = regs->regs[insn.spec3_format.rt];
+ StoreHWE(addr, value, res);
+ if (res) {
+ set_fs(seg);
+ goto fault;
+ }
+ break;
+ case swe_op:
+ if (!access_ok(VERIFY_WRITE, addr, 4)) {
+ set_fs(seg);
+ goto sigbus;
+ }
+ compute_return_epc(regs);
+ value = regs->regs[insn.spec3_format.rt];
+ StoreWE(addr, value, res);
+ if (res) {
+ set_fs(seg);
+ goto fault;
+ }
+ break;
+ default:
set_fs(seg);
- goto fault;
+ goto sigill;
}
- break;
- default:
set_fs(seg);
- goto sigill;
}
- set_fs(seg);
- break;
#endif
+ break;
case lh_op:
if (!access_ok(VERIFY_READ, addr, 2))
goto sigbus;
--
2.7.4
