[PATCH v2 0/4] target/mips: misc microMIPS fixes

[PATCH v2 0/4] target/mips: misc microMIPS fixes

[Marcin Nowakowski]

v2:
  - add reviewed-by to patch 1 & 2
  - add CP0.Config7.WII for P5600
  - new patch: add CP0.Config[4,5] for M14K(c)

Marcin Nowakowski (4):
  target/mips: fix JALS32/J32 instruction handling for microMIPS
  target/mips: fix SWM32 handling for micromips
  target/mips: implement CP0.Config7.WII bit support
  target/mips: set correct CP0.Config[4,5] values for M14K(c)

 target/mips/cpu-defs.c.inc    | 13 +++++++++++--
 target/mips/cpu.c             |  6 ++++--
 target/mips/cpu.h             |  1 +
 target/mips/tcg/ldst_helper.c |  4 ++--
 target/mips/tcg/translate.c   |  7 +++++++
 5 files changed, 25 insertions(+), 6 deletions(-)

-- 
2.25.1

[PATCH v2 1/4] target/mips: fix JALS32/J32 instruction handling for microMIPS

[Marcin Nowakowski]

microMIPS J & JAL instructions perform a jump in a 128MB region and 5
top bits of the address need to be preserved. This is different behavior
compared to standard mips systems, where the jump is executed within a
256MB region.
Note that microMIPS32 instruction set documentation appears to have
inconsistent information regarding JALX32 instruction - it is written in
the doc that:

"To execute a procedure call within the current 256 MB-aligned region
(...)
The low 26 bits of the target address is the target field shifted left
2 bits."

But the target address is already 26 bits. Moreover, the operation
description indicates that 28 bits are copied, so the statement about
use of 26 bits is _most likely_ incorrect and the corresponding code
remains the same as for standard mips instruction set.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/mips/tcg/translate.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/target/mips/tcg/translate.c b/target/mips/tcg/translate.c
index 624e6b7786..567ca11ccf 100644
--- a/target/mips/tcg/translate.c
+++ b/target/mips/tcg/translate.c
@@ -4917,6 +4917,13 @@ static void gen_compute_branch(DisasContext *ctx, uint32_t opc,
         break;
     case OPC_J:
     case OPC_JAL:
+        {
+            /* Jump to immediate */
+            int jal_mask = ctx->hflags & MIPS_HFLAG_M16 ? 0xF8000000 : 0xF0000000;
+            btgt = ((ctx->base.pc_next + insn_bytes) & jal_mask) |
+                (uint32_t)offset;
+            break;
+        }
     case OPC_JALX:
         /* Jump to immediate */
         btgt = ((ctx->base.pc_next + insn_bytes) & (int32_t)0xF0000000) |
-- 
2.25.1

[PATCH v2 2/4] target/mips: fix SWM32 handling for micromips

[Marcin Nowakowski]

SWM32 should store a sequence of 32-bit words from the GPRs, but it was
incorrectly coded to store 16-bit words only. As a result, an LWM32 that
usually follows would restore invalid register values.

Fixes: 7dd547e5ab ("target/mips: Use cpu_*_mmuidx_ra instead of
MMU_MODE*_SUFFIX")

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 target/mips/tcg/ldst_helper.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/target/mips/tcg/ldst_helper.c b/target/mips/tcg/ldst_helper.c
index d0bd0267b2..c1a8380e34 100644
--- a/target/mips/tcg/ldst_helper.c
+++ b/target/mips/tcg/ldst_helper.c
@@ -248,14 +248,14 @@ void helper_swm(CPUMIPSState *env, target_ulong addr, target_ulong reglist,
         target_ulong i;
 
         for (i = 0; i < base_reglist; i++) {
-            cpu_stw_mmuidx_ra(env, addr, env->active_tc.gpr[multiple_regs[i]],
+            cpu_stl_mmuidx_ra(env, addr, env->active_tc.gpr[multiple_regs[i]],
                               mem_idx, GETPC());
             addr += 4;
         }
     }
 
     if (do_r31) {
-        cpu_stw_mmuidx_ra(env, addr, env->active_tc.gpr[31], mem_idx, GETPC());
+        cpu_stl_mmuidx_ra(env, addr, env->active_tc.gpr[31], mem_idx, GETPC());
     }
 }
 
-- 
2.25.1

[PATCH v2 3/4] target/mips: implement CP0.Config7.WII bit support

[Marcin Nowakowski]

Some pre-release 6 cores use CP0.Config7.WII bit to indicate that a
disabled interrupt should wake up a sleeping CPU.
Enable this bit by default for M14K(c) and P5600. There are potentially
other cores that support this feature, but I do not have a complete
list.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
---
 target/mips/cpu-defs.c.inc | 3 +++
 target/mips/cpu.c          | 6 ++++--
 target/mips/cpu.h          | 1 +
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/target/mips/cpu-defs.c.inc b/target/mips/cpu-defs.c.inc
index 480e60aeec..fdde04dfb9 100644
--- a/target/mips/cpu-defs.c.inc
+++ b/target/mips/cpu-defs.c.inc
@@ -333,6 +333,7 @@ const mips_def_t mips_defs[] =
         .CP0_Config1 = MIPS_CONFIG1,
         .CP0_Config2 = MIPS_CONFIG2,
         .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (1 << CP0C3_VInt),
+        .CP0_Config7 = 1 << CP0C7_WII,
         .CP0_LLAddr_rw_bitmask = 0,
         .CP0_LLAddr_shift = 4,
         .SYNCI_Step = 32,
@@ -354,6 +355,7 @@ const mips_def_t mips_defs[] =
                        (0 << CP0C1_DS) | (3 << CP0C1_DL) | (1 << CP0C1_DA),
         .CP0_Config2 = MIPS_CONFIG2,
         .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (0 << CP0C3_VInt),
+        .CP0_Config7 = 1 << CP0C7_WII,
         .CP0_LLAddr_rw_bitmask = 0,
         .CP0_LLAddr_shift = 4,
         .SYNCI_Step = 32,
@@ -392,6 +394,7 @@ const mips_def_t mips_defs[] =
         .CP0_Config5_rw_bitmask = (1 << CP0C5_K) | (1 << CP0C5_CV) |
                                   (1 << CP0C5_MSAEn) | (1 << CP0C5_UFE) |
                                   (1 << CP0C5_FRE) | (1 << CP0C5_UFR),
+        .CP0_Config7 = 1 << CP0C7_WII,
         .CP0_LLAddr_rw_bitmask = 0,
         .CP0_LLAddr_shift = 0,
         .SYNCI_Step = 32,
diff --git a/target/mips/cpu.c b/target/mips/cpu.c
index 7a565466cb..7ba359696f 100644
--- a/target/mips/cpu.c
+++ b/target/mips/cpu.c
@@ -144,12 +144,14 @@ static bool mips_cpu_has_work(CPUState *cs)
     /*
      * Prior to MIPS Release 6 it is implementation dependent if non-enabled
      * interrupts wake-up the CPU, however most of the implementations only
-     * check for interrupts that can be taken.
+     * check for interrupts that can be taken. For pre-release 6 CPUs,
+     * check for CP0 Config7 'Wait IE ignore' bit.
      */
     if ((cs->interrupt_request & CPU_INTERRUPT_HARD) &&
         cpu_mips_hw_interrupts_pending(env)) {
         if (cpu_mips_hw_interrupts_enabled(env) ||
-            (env->insn_flags & ISA_MIPS_R6)) {
+            (env->insn_flags & ISA_MIPS_R6) ||
+            (env->CP0_Config7 & (1 << CP0C7_WII))) {
             has_work = true;
         }
     }
diff --git a/target/mips/cpu.h b/target/mips/cpu.h
index 0a085643a3..abee7a99d7 100644
--- a/target/mips/cpu.h
+++ b/target/mips/cpu.h
@@ -980,6 +980,7 @@ typedef struct CPUArchState {
 #define CP0C6_DATAPREF        0
     int32_t CP0_Config7;
     int64_t CP0_Config7_rw_bitmask;
+#define CP0C7_WII          31
 #define CP0C7_NAPCGEN       2
 #define CP0C7_UNIMUEN       1
 #define CP0C7_VFPUCGEN      0
-- 
2.25.1

Re: [PATCH v2 3/4] target/mips: implement CP0.Config7.WII bit support

[Philippe Mathieu-Daudé]

On 16/2/23 06:17, Marcin Nowakowski wrote:
> Some pre-release 6 cores use CP0.Config7.WII bit to indicate that a
> disabled interrupt should wake up a sleeping CPU.
> Enable this bit by default for M14K(c) and P5600. There are potentially
> other cores that support this feature, but I do not have a complete
> list.
> 
> Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
> ---
>   target/mips/cpu-defs.c.inc | 3 +++
>   target/mips/cpu.c          | 6 ++++--
>   target/mips/cpu.h          | 1 +
>   3 files changed, 8 insertions(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

[PATCH v2 4/4] target/mips: set correct CP0.Config[4, 5] values for M14K(c)

[Marcin Nowakowski]

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 target/mips/cpu-defs.c.inc | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/target/mips/cpu-defs.c.inc b/target/mips/cpu-defs.c.inc
index fdde04dfb9..d45f245a67 100644
--- a/target/mips/cpu-defs.c.inc
+++ b/target/mips/cpu-defs.c.inc
@@ -332,7 +332,10 @@ const mips_def_t mips_defs[] =
                        (0x1 << CP0C0_AR) | (MMU_TYPE_FMT << CP0C0_MT),
         .CP0_Config1 = MIPS_CONFIG1,
         .CP0_Config2 = MIPS_CONFIG2,
-        .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (1 << CP0C3_VInt),
+        .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (1 << CP0C3_VInt) |
+                       (1 << CP0C3_M),
+        .CP0_Config4 = MIPS_CONFIG4 | (1 << CP0C4_M),
+        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_NFExists),
         .CP0_Config7 = 1 << CP0C7_WII,
         .CP0_LLAddr_rw_bitmask = 0,
         .CP0_LLAddr_shift = 4,
@@ -354,7 +357,10 @@ const mips_def_t mips_defs[] =
                        (0 << CP0C1_IS) | (3 << CP0C1_IL) | (1 << CP0C1_IA) |
                        (0 << CP0C1_DS) | (3 << CP0C1_DL) | (1 << CP0C1_DA),
         .CP0_Config2 = MIPS_CONFIG2,
-        .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (0 << CP0C3_VInt),
+        .CP0_Config3 = MIPS_CONFIG3 | (0x2 << CP0C3_ISA) | (0 << CP0C3_VInt) |
+                       (1 << CP0C3_M),
+        .CP0_Config4 = MIPS_CONFIG4 | (1 << CP0C4_M),
+        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_NFExists),
         .CP0_Config7 = 1 << CP0C7_WII,
         .CP0_LLAddr_rw_bitmask = 0,
         .CP0_LLAddr_shift = 4,
-- 
2.25.1

Re: [PATCH v2 4/4] target/mips: set correct CP0.Config[4,5] values for M14K(c)

[Philippe Mathieu-Daudé]

On 16/2/23 06:17, Marcin Nowakowski wrote:
> Signed-off-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
> Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   target/mips/cpu-defs.c.inc | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Re: [PATCH v2 0/4] target/mips: misc microMIPS fixes

[Philippe Mathieu-Daudé]

> Marcin Nowakowski (4):
>    target/mips: fix JALS32/J32 instruction handling for microMIPS
>    target/mips: fix SWM32 handling for micromips
>    target/mips: implement CP0.Config7.WII bit support
>    target/mips: set correct CP0.Config[4,5] values for M14K(c)

Merged as commits 9055ffd76e..dcebb36eb0.