2023-01-09 09:28:38

by Youling Tang

Subject: [PATCH 2/4] LoongArch: Add JUMP_LINK_ADDR macro implementation to avoid using la.abs

Add JUMP_LINK_ADDR macro implementation to avoid using la.abs.

Signed-off-by: Youling Tang <[email protected]>
---
arch/loongarch/include/asm/stackframe.h | 8 ++++++++
arch/loongarch/kernel/head.S | 10 ++++------
arch/loongarch/power/suspend_asm.S | 5 ++---
3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/arch/loongarch/include/asm/stackframe.h b/arch/loongarch/include/asm/stackframe.h
index 96c94035b5d0..f538b3a6d680 100644
--- a/arch/loongarch/include/asm/stackframe.h
+++ b/arch/loongarch/include/asm/stackframe.h
@@ -216,4 +216,12 @@
RESTORE_SP_AND_RET \docfi
.endm

+/* Jump to the virtual address of the link. */
+ .macro JUMP_LINK_ADDR
+ li.d t0, CACHE_BASE
+ pcaddi t1, 0
+ or t0, t0, t1
+ jirl zero, t0, 0xc
+ .endm
+
#endif /* _ASM_STACKFRAME_H */
diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
index aa6181714ec3..e8a4bf9d7599 100644
--- a/arch/loongarch/kernel/head.S
+++ b/arch/loongarch/kernel/head.S
@@ -52,9 +52,8 @@ SYM_CODE_START(kernel_entry) # kernel entry point

/* We might not get launched at the address the kernel is linked to,
so we jump there. */
- la.abs t0, 0f
- jr t0
-0:
+ JUMP_LINK_ADDR
+
/* Enable PG */
li.w t0, 0xb0 # PLV=0, IE=0, PG=1
csrwr t0, LOONGARCH_CSR_CRMD
@@ -106,9 +105,8 @@ SYM_CODE_START(smpboot_entry)
li.d t0, CSR_DMW1_INIT # CA, PLV0
csrwr t0, LOONGARCH_CSR_DMWIN1

- la.abs t0, 0f
- jr t0
-0:
+ JUMP_LINK_ADDR
+
/* Enable PG */
li.w t0, 0xb0 # PLV=0, IE=0, PG=1
csrwr t0, LOONGARCH_CSR_CRMD
diff --git a/arch/loongarch/power/suspend_asm.S b/arch/loongarch/power/suspend_asm.S
index eb2675642f9f..596a682a7924 100644
--- a/arch/loongarch/power/suspend_asm.S
+++ b/arch/loongarch/power/suspend_asm.S
@@ -78,9 +78,8 @@ SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
li.d t0, CSR_DMW1_INIT # CA, PLV0
csrwr t0, LOONGARCH_CSR_DMWIN1

- la.abs t0, 0f
- jr t0
-0:
+ JUMP_LINK_ADDR
+
la.pcrel t0, acpi_saved_sp
ld.d sp, t0, 0
SETUP_WAKEUP
--
2.37.1

2023-01-14 07:11:06

by Jinyang He

Subject: Re: [PATCH 2/4] LoongArch: Add JUMP_LINK_ADDR macro implementation to avoid using la.abs

On 2023-01-09 17:07, Youling Tang wrote:
> Add JUMP_LINK_ADDR macro implementation to avoid using la.abs.
>
> Signed-off-by: Youling Tang <[email protected]>
> ---
> arch/loongarch/include/asm/stackframe.h | 8 ++++++++
> arch/loongarch/kernel/head.S | 10 ++++------
> arch/loongarch/power/suspend_asm.S | 5 ++---
> 3 files changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/arch/loongarch/include/asm/stackframe.h b/arch/loongarch/include/asm/stackframe.h
> index 96c94035b5d0..f538b3a6d680 100644
> --- a/arch/loongarch/include/asm/stackframe.h
> +++ b/arch/loongarch/include/asm/stackframe.h
> @@ -216,4 +216,12 @@
> RESTORE_SP_AND_RET \docfi
> .endm
>
> +/* Jump to the virtual address of the link. */
> + .macro JUMP_LINK_ADDR

Hi, Youling


IMHO the JUMP_CACHE_ADDR is more suitable. And it not clear higt bits,
although the result always true currently. Lastly, this macro clobbers
t0 and t1, I'd suggest pass them in as args.


Thanks,

Jinyang

> + li.d t0, CACHE_BASE
> + pcaddi t1, 0
> + or t0, t0, t1
> + jirl zero, t0, 0xc
> + .endm
> +
> #endif /* _ASM_STACKFRAME_H */
> diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
> index aa6181714ec3..e8a4bf9d7599 100644
> --- a/arch/loongarch/kernel/head.S
> +++ b/arch/loongarch/kernel/head.S
> @@ -52,9 +52,8 @@ SYM_CODE_START(kernel_entry) # kernel entry point
>
> /* We might not get launched at the address the kernel is linked to,
> so we jump there. */
> - la.abs t0, 0f
> - jr t0
> -0:
> + JUMP_LINK_ADDR
> +
> /* Enable PG */
> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
> csrwr t0, LOONGARCH_CSR_CRMD
> @@ -106,9 +105,8 @@ SYM_CODE_START(smpboot_entry)
> li.d t0, CSR_DMW1_INIT # CA, PLV0
> csrwr t0, LOONGARCH_CSR_DMWIN1
>
> - la.abs t0, 0f
> - jr t0
> -0:
> + JUMP_LINK_ADDR
> +
> /* Enable PG */
> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
> csrwr t0, LOONGARCH_CSR_CRMD
> diff --git a/arch/loongarch/power/suspend_asm.S b/arch/loongarch/power/suspend_asm.S
> index eb2675642f9f..596a682a7924 100644
> --- a/arch/loongarch/power/suspend_asm.S
> +++ b/arch/loongarch/power/suspend_asm.S
> @@ -78,9 +78,8 @@ SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
> li.d t0, CSR_DMW1_INIT # CA, PLV0
> csrwr t0, LOONGARCH_CSR_DMWIN1
>
> - la.abs t0, 0f
> - jr t0
> -0:
> + JUMP_LINK_ADDR
> +
> la.pcrel t0, acpi_saved_sp
> ld.d sp, t0, 0
> SETUP_WAKEUP

2023-01-14 07:58:17

by Youling Tang

Subject: Re: [PATCH 2/4] LoongArch: Add JUMP_LINK_ADDR macro implementation to avoid using la.abs

Hi, Jinyang

On 01/14/2023 02:40 PM, Jinyang He wrote:
>
> On 2023-01-09 17:07, Youling Tang wrote:
>> Add JUMP_LINK_ADDR macro implementation to avoid using la.abs.
>>
>> Signed-off-by: Youling Tang <[email protected]>
>> ---
>> arch/loongarch/include/asm/stackframe.h | 8 ++++++++
>> arch/loongarch/kernel/head.S | 10 ++++------
>> arch/loongarch/power/suspend_asm.S | 5 ++---
>> 3 files changed, 14 insertions(+), 9 deletions(-)
>>
>> diff --git a/arch/loongarch/include/asm/stackframe.h
>> b/arch/loongarch/include/asm/stackframe.h
>> index 96c94035b5d0..f538b3a6d680 100644
>> --- a/arch/loongarch/include/asm/stackframe.h
>> +++ b/arch/loongarch/include/asm/stackframe.h
>> @@ -216,4 +216,12 @@
>> RESTORE_SP_AND_RET \docfi
>> .endm
>> +/* Jump to the virtual address of the link. */
>> + .macro JUMP_LINK_ADDR
>
> Hi, Youling
>
>
> IMHO the JUMP_CACHE_ADDR is more suitable. And it not clear higt bits,
> although the result always true currently. Lastly, this macro clobbers
> t0 and t1, I'd suggest pass them in as args.

Ok, I will modify it as follows：

.macro JUMP_CACHE_ADDR temp1 temp2
li.d \temp1, CACHE_BASE
pcaddi \temp2, 0
or \temp1, \temp1, \temp2
jirl zero, \temp1, 0xc
.endm

There is also an alternative name "JUMP_DMW1_ADDR" for discussion.

Thanks,
Youling

>
>
> Thanks,
>
> Jinyang
>
>> + li.d t0, CACHE_BASE
>> + pcaddi t1, 0
>> + or t0, t0, t1
>> + jirl zero, t0, 0xc
>> + .endm
>> +
>> #endif /* _ASM_STACKFRAME_H */
>> diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
>> index aa6181714ec3..e8a4bf9d7599 100644
>> --- a/arch/loongarch/kernel/head.S
>> +++ b/arch/loongarch/kernel/head.S
>> @@ -52,9 +52,8 @@ SYM_CODE_START(kernel_entry) # kernel
>> entry point
>> /* We might not get launched at the address the kernel is
>> linked to,
>> so we jump there. */
>> - la.abs t0, 0f
>> - jr t0
>> -0:
>> + JUMP_LINK_ADDR
>> +
>> /* Enable PG */
>> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
>> csrwr t0, LOONGARCH_CSR_CRMD
>> @@ -106,9 +105,8 @@ SYM_CODE_START(smpboot_entry)
>> li.d t0, CSR_DMW1_INIT # CA, PLV0
>> csrwr t0, LOONGARCH_CSR_DMWIN1
>> - la.abs t0, 0f
>> - jr t0
>> -0:
>> + JUMP_LINK_ADDR
>> +
>> /* Enable PG */
>> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
>> csrwr t0, LOONGARCH_CSR_CRMD
>> diff --git a/arch/loongarch/power/suspend_asm.S
>> b/arch/loongarch/power/suspend_asm.S
>> index eb2675642f9f..596a682a7924 100644
>> --- a/arch/loongarch/power/suspend_asm.S
>> +++ b/arch/loongarch/power/suspend_asm.S
>> @@ -78,9 +78,8 @@ SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
>> li.d t0, CSR_DMW1_INIT # CA, PLV0
>> csrwr t0, LOONGARCH_CSR_DMWIN1
>> - la.abs t0, 0f
>> - jr t0
>> -0:
>> + JUMP_LINK_ADDR
>> +
>> la.pcrel t0, acpi_saved_sp
>> ld.d sp, t0, 0
>> SETUP_WAKEUP
>

2023-01-14 08:28:51

by Huacai Chen

Subject: Re: [PATCH 2/4] LoongArch: Add JUMP_LINK_ADDR macro implementation to avoid using la.abs

But JUMP_LINK_ADDR looks fine to me. :)

Huacai

On Sat, Jan 14, 2023 at 3:25 PM Youling Tang <[email protected]> wrote:
>
> Hi, Jinyang
>
> On 01/14/2023 02:40 PM, Jinyang He wrote:
> >
> > On 2023-01-09 17:07, Youling Tang wrote:
> >> Add JUMP_LINK_ADDR macro implementation to avoid using la.abs.
> >>
> >> Signed-off-by: Youling Tang <[email protected]>
> >> ---
> >> arch/loongarch/include/asm/stackframe.h | 8 ++++++++
> >> arch/loongarch/kernel/head.S | 10 ++++------
> >> arch/loongarch/power/suspend_asm.S | 5 ++---
> >> 3 files changed, 14 insertions(+), 9 deletions(-)
> >>
> >> diff --git a/arch/loongarch/include/asm/stackframe.h
> >> b/arch/loongarch/include/asm/stackframe.h
> >> index 96c94035b5d0..f538b3a6d680 100644
> >> --- a/arch/loongarch/include/asm/stackframe.h
> >> +++ b/arch/loongarch/include/asm/stackframe.h
> >> @@ -216,4 +216,12 @@
> >> RESTORE_SP_AND_RET \docfi
> >> .endm
> >> +/* Jump to the virtual address of the link. */
> >> + .macro JUMP_LINK_ADDR
> >
> > Hi, Youling
> >
> >
> > IMHO the JUMP_CACHE_ADDR is more suitable. And it not clear higt bits,
> > although the result always true currently. Lastly, this macro clobbers
> > t0 and t1, I'd suggest pass them in as args.
>
> Ok, I will modify it as follows：
>
> .macro JUMP_CACHE_ADDR temp1 temp2
> li.d \temp1, CACHE_BASE
> pcaddi \temp2, 0
> or \temp1, \temp1, \temp2
> jirl zero, \temp1, 0xc
> .endm
>
> There is also an alternative name "JUMP_DMW1_ADDR" for discussion.
>
> Thanks,
> Youling
>
> >
> >
> > Thanks,
> >
> > Jinyang
> >
> >> + li.d t0, CACHE_BASE
> >> + pcaddi t1, 0
> >> + or t0, t0, t1
> >> + jirl zero, t0, 0xc
> >> + .endm
> >> +
> >> #endif /* _ASM_STACKFRAME_H */
> >> diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
> >> index aa6181714ec3..e8a4bf9d7599 100644
> >> --- a/arch/loongarch/kernel/head.S
> >> +++ b/arch/loongarch/kernel/head.S
> >> @@ -52,9 +52,8 @@ SYM_CODE_START(kernel_entry) # kernel
> >> entry point
> >> /* We might not get launched at the address the kernel is
> >> linked to,
> >> so we jump there. */
> >> - la.abs t0, 0f
> >> - jr t0
> >> -0:
> >> + JUMP_LINK_ADDR
> >> +
> >> /* Enable PG */
> >> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
> >> csrwr t0, LOONGARCH_CSR_CRMD
> >> @@ -106,9 +105,8 @@ SYM_CODE_START(smpboot_entry)
> >> li.d t0, CSR_DMW1_INIT # CA, PLV0
> >> csrwr t0, LOONGARCH_CSR_DMWIN1
> >> - la.abs t0, 0f
> >> - jr t0
> >> -0:
> >> + JUMP_LINK_ADDR
> >> +
> >> /* Enable PG */
> >> li.w t0, 0xb0 # PLV=0, IE=0, PG=1
> >> csrwr t0, LOONGARCH_CSR_CRMD
> >> diff --git a/arch/loongarch/power/suspend_asm.S
> >> b/arch/loongarch/power/suspend_asm.S
> >> index eb2675642f9f..596a682a7924 100644
> >> --- a/arch/loongarch/power/suspend_asm.S
> >> +++ b/arch/loongarch/power/suspend_asm.S
> >> @@ -78,9 +78,8 @@ SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
> >> li.d t0, CSR_DMW1_INIT # CA, PLV0
> >> csrwr t0, LOONGARCH_CSR_DMWIN1
> >> - la.abs t0, 0f
> >> - jr t0
> >> -0:
> >> + JUMP_LINK_ADDR
> >> +
> >> la.pcrel t0, acpi_saved_sp
> >> ld.d sp, t0, 0
> >> SETUP_WAKEUP
> >
>