[PATCH AUTOSEL 4.4 65/65] MIPS: DEC: Fix an int-handler.S CPU_DADDI_WORKAROUNDS regression

Sasha Levin
2018-10-25T14:18:50Z

From: "Maciej W. Rozycki" <macro@linux-mips.org>

[ Upstream commit 68fe55680d0f3342969f49412fceabb90bdfadba ]

Fix a commit 3021773c7c3e ("MIPS: DEC: Avoid la pseudo-instruction in
delay slots") regression and remove assembly errors:

arch/mips/dec/int-handler.S: Assembler messages:
arch/mips/dec/int-handler.S:162: Error: Macro used $at after ".set noat"
arch/mips/dec/int-handler.S:163: Error: Macro used $at after ".set noat"
arch/mips/dec/int-handler.S:229: Error: Macro used $at after ".set noat"
arch/mips/dec/int-handler.S:230: Error: Macro used $at after ".set noat"

triggering with with the CPU_DADDI_WORKAROUNDS option set and the DADDIU
instruction. This is because with that option in place the instruction
becomes a macro, which expands to an LI/DADDU (or actually ADDIU/DADDU)
sequence that uses $at as a temporary register.

With CPU_DADDI_WORKAROUNDS we only support `-msym32' compilation though,
and this is already enforced in arch/mips/Makefile, so choose the 32-bit
expansion variant for the supported configurations and then replace the
64-bit variant with #error just in case.

Fixes: 3021773c7c3e ("MIPS: DEC: Avoid la pseudo-instruction in delay slots")
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.8+
Patchwork: https://patchwork.linux-mips.org/patch/16893/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/mips/dec/int-handler.S | 34 ++++++----------------------------
1 file changed, 6 insertions(+), 28 deletions(-)

diff --git a/arch/mips/dec/int-handler.S b/arch/mips/dec/int-handler.S
index 554d1da97743..21f4a9fe82fa 100644
--- a/arch/mips/dec/int-handler.S
+++ b/arch/mips/dec/int-handler.S
@@ -147,23 +147,12 @@
* Find irq with highest priority
*/
# open coded PTR_LA t1, cpu_mask_nr_tbl
-#if (_MIPS_SZPTR == 32)
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
# open coded la t1, cpu_mask_nr_tbl
lui t1, %hi(cpu_mask_nr_tbl)
addiu t1, %lo(cpu_mask_nr_tbl)
-
-#endif
-#if (_MIPS_SZPTR == 64)
- # open coded dla t1, cpu_mask_nr_tbl
- .set push
- .set noat
- lui t1, %highest(cpu_mask_nr_tbl)
- lui AT, %hi(cpu_mask_nr_tbl)
- daddiu t1, t1, %higher(cpu_mask_nr_tbl)
- daddiu AT, AT, %lo(cpu_mask_nr_tbl)
- dsll t1, 32
- daddu t1, t1, AT
- .set pop
+#else
+#error GCC `-msym32' option required for 64-bit DECstation builds
#endif
1: lw t2,(t1)
nop
@@ -214,23 +203,12 @@
* Find irq with highest priority
*/
# open coded PTR_LA t1,asic_mask_nr_tbl
-#if (_MIPS_SZPTR == 32)
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
# open coded la t1, asic_mask_nr_tbl
lui t1, %hi(asic_mask_nr_tbl)
addiu t1, %lo(asic_mask_nr_tbl)
-
-#endif
-#if (_MIPS_SZPTR == 64)
- # open coded dla t1, asic_mask_nr_tbl
- .set push
- .set noat
- lui t1, %highest(asic_mask_nr_tbl)
- lui AT, %hi(asic_mask_nr_tbl)
- daddiu t1, t1, %higher(asic_mask_nr_tbl)
- daddiu AT, AT, %lo(asic_mask_nr_tbl)
- dsll t1, 32
- daddu t1, t1, AT
- .set pop
+#else
+#error GCC `-msym32' option required for 64-bit DECstation builds
#endif
2: lw t2,(t1)
nop
--
2.17.1