* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
@ 2017-01-13 7:50 Alison Wang
2017-01-13 8:11 ` Alexander Graf
2017-01-13 8:16 ` Alison Wang
0 siblings, 2 replies; 9+ messages in thread
From: Alison Wang @ 2017-01-13 7:50 UTC (permalink / raw)
To: u-boot
For 64-bit kernel, there is a warning about x1-x3 nonzero in violation
of boot protocol. x3 should be reset to zero before jumping to the
kernel.
This patch will adjust the parameters to transfer and make sure x3 is
zero.
Signed-off-by: Alison Wang <alison.wang@nxp.com>
---
arch/arm/cpu/armv8/transition.S | 44 +++++++++++++++++++++++++++++++++++++----
1 file changed, 40 insertions(+), 4 deletions(-)
diff --git a/arch/arm/cpu/armv8/transition.S b/arch/arm/cpu/armv8/transition.S
index adb9f35..06b6664 100644
--- a/arch/arm/cpu/armv8/transition.S
+++ b/arch/arm/cpu/armv8/transition.S
@@ -26,9 +26,27 @@ ENTRY(armv8_switch_to_el2)
* if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
* When running in EL2 now, jump to the
* address saved in x3.
+ *
+ * For 64-bit kernel, there is a warning about
+ * x1-x3 nonzero in violation of boot protocol.
+ * x3 should be reset to zero before jumping to
+ * the kernel. Use x4 instead of x3 as parameter.
*/
- br x3
-1: armv8_switch_to_el2_m x3, x4, x5
+ mov x4, x3
+ mov x3, #0
+ br x4
+1:
+ /*
+ * For 64-bit kernel, there is a warning about
+ * x1-x3 nonzero in violation of boot protocol.
+ * x3 should be reset to zero before jumping to
+ * the kernel. Use x4, x5, x6 instead of x3, x4,
+ * x5 as parameters.
+ */
+ mov x5, x4
+ mov x4, x3
+ mov x3, #0
+ armv8_switch_to_el2_m x4, x5, x6
ENDPROC(armv8_switch_to_el2)
ENTRY(armv8_switch_to_el1)
@@ -36,9 +54,27 @@ ENTRY(armv8_switch_to_el1)
0:
/* x3 is kernel entry point. When running in EL1
* now, jump to the address saved in x3.
+ *
+ * For 64-bit kernel, there is a warning about
+ * x1-x3 nonzero in violation of boot protocol.
+ * x3 should be reset to zero before jumping to
+ * the kernel. Use x4 instead of x3 as parameter.
+ */
+ mov x4, x3
+ mov x3, #0
+ br x4
+1:
+ /*
+ * For 64-bit kernel, there is a warning about
+ * x1-x3 nonzero in violation of boot protocol.
+ * x3 should be reset to zero before jumping to
+ * the kernel. Use x4, x5, x6 instead of x3, x4,
+ * x5 as parameters.
*/
- br x3
-1: armv8_switch_to_el1_m x3, x4, x5
+ mov x5, x4
+ mov x4, x3
+ mov x3, #0
+ armv8_switch_to_el1_m x4, x5, x6
ENDPROC(armv8_switch_to_el1)
WEAK(armv8_el2_to_aarch32)
--
2.1.0.27.g96db324
^ permalink raw reply related [flat|nested] 9+ messages in thread* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 7:50 [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue Alison Wang
@ 2017-01-13 8:11 ` Alexander Graf
2017-01-13 8:23 ` Alison Wang
2017-01-13 8:16 ` Alison Wang
1 sibling, 1 reply; 9+ messages in thread
From: Alexander Graf @ 2017-01-13 8:11 UTC (permalink / raw)
To: u-boot
> Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
>
> For 64-bit kernel, there is a warning about x1-x3 nonzero in violation
> of boot protocol. x3 should be reset to zero before jumping to the
> kernel.
>
> This patch will adjust the parameters to transfer and make sure x3 is
> zero.
>
> Signed-off-by: Alison Wang <alison.wang@nxp.com>
If x3 is part of the boot protocol, please treat it as function argument rather than hard code it to 0.
Alex
> ---
> arch/arm/cpu/armv8/transition.S | 44 +++++++++++++++++++++++++++++++++++++----
> 1 file changed, 40 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/cpu/armv8/transition.S b/arch/arm/cpu/armv8/transition.S
> index adb9f35..06b6664 100644
> --- a/arch/arm/cpu/armv8/transition.S
> +++ b/arch/arm/cpu/armv8/transition.S
> @@ -26,9 +26,27 @@ ENTRY(armv8_switch_to_el2)
> * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
> * When running in EL2 now, jump to the
> * address saved in x3.
> + *
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4 instead of x3 as parameter.
> */
> - br x3
> -1: armv8_switch_to_el2_m x3, x4, x5
> + mov x4, x3
> + mov x3, #0
> + br x4
> +1:
> + /*
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4, x5, x6 instead of x3, x4,
> + * x5 as parameters.
> + */
> + mov x5, x4
> + mov x4, x3
> + mov x3, #0
> + armv8_switch_to_el2_m x4, x5, x6
> ENDPROC(armv8_switch_to_el2)
>
> ENTRY(armv8_switch_to_el1)
> @@ -36,9 +54,27 @@ ENTRY(armv8_switch_to_el1)
> 0:
> /* x3 is kernel entry point. When running in EL1
> * now, jump to the address saved in x3.
> + *
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4 instead of x3 as parameter.
> + */
> + mov x4, x3
> + mov x3, #0
> + br x4
> +1:
> + /*
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4, x5, x6 instead of x3, x4,
> + * x5 as parameters.
> */
> - br x3
> -1: armv8_switch_to_el1_m x3, x4, x5
> + mov x5, x4
> + mov x4, x3
> + mov x3, #0
> + armv8_switch_to_el1_m x4, x5, x6
> ENDPROC(armv8_switch_to_el1)
>
> WEAK(armv8_el2_to_aarch32)
> --
> 2.1.0.27.g96db324
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 8:11 ` Alexander Graf
@ 2017-01-13 8:23 ` Alison Wang
2017-01-13 8:33 ` Alexander Graf
0 siblings, 1 reply; 9+ messages in thread
From: Alison Wang @ 2017-01-13 8:23 UTC (permalink / raw)
To: u-boot
> > Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
> >
> > For 64-bit kernel, there is a warning about x1-x3 nonzero in
> violation
> > of boot protocol. x3 should be reset to zero before jumping to the
> > kernel.
> >
> > This patch will adjust the parameters to transfer and make sure x3 is
> > zero.
> >
> > Signed-off-by: Alison Wang <alison.wang@nxp.com>
>
> If x3 is part of the boot protocol, please treat it as function
> argument rather than hard code it to 0.
>
[Alison Wang] I think x3 need to set to 0. Refer to the codes for the warning in kernel,
if (boot_args[1] || boot_args[2] || boot_args[3]) {
pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n"
"\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
"This indicates a broken bootloader or old kernel\n",
boot_args[1], boot_args[2], boot_args[3]);
}
>
> > ---
> > arch/arm/cpu/armv8/transition.S | 44
> > +++++++++++++++++++++++++++++++++++++----
> > 1 file changed, 40 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/arm/cpu/armv8/transition.S
> > b/arch/arm/cpu/armv8/transition.S index adb9f35..06b6664 100644
> > --- a/arch/arm/cpu/armv8/transition.S
> > +++ b/arch/arm/cpu/armv8/transition.S
> > @@ -26,9 +26,27 @@ ENTRY(armv8_switch_to_el2)
> > * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
> > * When running in EL2 now, jump to the
> > * address saved in x3.
> > + *
> > + * For 64-bit kernel, there is a warning about
> > + * x1-x3 nonzero in violation of boot protocol.
> > + * x3 should be reset to zero before jumping to
> > + * the kernel. Use x4 instead of x3 as parameter.
> > */
> > - br x3
> > -1: armv8_switch_to_el2_m x3, x4, x5
> > + mov x4, x3
> > + mov x3, #0
> > + br x4
> > +1:
> > + /*
> > + * For 64-bit kernel, there is a warning about
> > + * x1-x3 nonzero in violation of boot protocol.
> > + * x3 should be reset to zero before jumping to
> > + * the kernel. Use x4, x5, x6 instead of x3, x4,
> > + * x5 as parameters.
> > + */
> > + mov x5, x4
> > + mov x4, x3
> > + mov x3, #0
> > + armv8_switch_to_el2_m x4, x5, x6
> > ENDPROC(armv8_switch_to_el2)
> >
> > ENTRY(armv8_switch_to_el1)
> > @@ -36,9 +54,27 @@ ENTRY(armv8_switch_to_el1)
> > 0:
> > /* x3 is kernel entry point. When running in EL1
> > * now, jump to the address saved in x3.
> > + *
> > + * For 64-bit kernel, there is a warning about
> > + * x1-x3 nonzero in violation of boot protocol.
> > + * x3 should be reset to zero before jumping to
> > + * the kernel. Use x4 instead of x3 as parameter.
> > + */
> > + mov x4, x3
> > + mov x3, #0
> > + br x4
> > +1:
> > + /*
> > + * For 64-bit kernel, there is a warning about
> > + * x1-x3 nonzero in violation of boot protocol.
> > + * x3 should be reset to zero before jumping to
> > + * the kernel. Use x4, x5, x6 instead of x3, x4,
> > + * x5 as parameters.
> > */
> > - br x3
> > -1: armv8_switch_to_el1_m x3, x4, x5
> > + mov x5, x4
> > + mov x4, x3
> > + mov x3, #0
> > + armv8_switch_to_el1_m x4, x5, x6
> > ENDPROC(armv8_switch_to_el1)
> >
> > WEAK(armv8_el2_to_aarch32)
> > --
> > 2.1.0.27.g96db324
> >
Best Regards,
Alison Wang
^ permalink raw reply [flat|nested] 9+ messages in thread* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 8:23 ` Alison Wang
@ 2017-01-13 8:33 ` Alexander Graf
2017-01-13 9:36 ` Alison Wang
0 siblings, 1 reply; 9+ messages in thread
From: Alexander Graf @ 2017-01-13 8:33 UTC (permalink / raw)
To: u-boot
On 01/13/2017 09:23 AM, Alison Wang wrote:
>>> Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
>>>
>>> For 64-bit kernel, there is a warning about x1-x3 nonzero in
>> violation
>>> of boot protocol. x3 should be reset to zero before jumping to the
>>> kernel.
>>>
>>> This patch will adjust the parameters to transfer and make sure x3 is
>>> zero.
>>>
>>> Signed-off-by: Alison Wang <alison.wang@nxp.com>
>> If x3 is part of the boot protocol, please treat it as function
>> argument rather than hard code it to 0.
>>
> [Alison Wang] I think x3 need to set to 0. Refer to the codes for the warning in kernel,
>
> if (boot_args[1] || boot_args[2] || boot_args[3]) {
> pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n"
> "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
> "This indicates a broken bootloader or old kernel\n",
> boot_args[1], boot_args[2], boot_args[3]);
> }
Yes, that merely means that the kernel doesn't take 3 arguments, it
takes 4. Today args[1..3] have to be 0, but I don't want to iron that
out in u-boot code.
So in pseudo-code, what we do today is we call
entry(dt_addr, 0, 0);
and instead we should be calling
entry(dt_addr, 0, 0, 0);
So in U-Boot code that means we should change the prototype for our
switch function from
void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
u64 entry_point, u64 es_flag);
to
void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
u64 arg4, u64 entry_point, u64 es_flag);
and adapt the macros accordingly to use x5/x6 instead of x4/5.
Alex
^ permalink raw reply [flat|nested] 9+ messages in thread* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 8:33 ` Alexander Graf
@ 2017-01-13 9:36 ` Alison Wang
2017-01-13 9:55 ` Alexander Graf
0 siblings, 1 reply; 9+ messages in thread
From: Alison Wang @ 2017-01-13 9:36 UTC (permalink / raw)
To: u-boot
> On 01/13/2017 09:23 AM, Alison Wang wrote:
> >>> Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
> >>>
> >>> For 64-bit kernel, there is a warning about x1-x3 nonzero in
> >> violation
> >>> of boot protocol. x3 should be reset to zero before jumping to the
> >>> kernel.
> >>>
> >>> This patch will adjust the parameters to transfer and make sure x3
> >>> is zero.
> >>>
> >>> Signed-off-by: Alison Wang <alison.wang@nxp.com>
> >> If x3 is part of the boot protocol, please treat it as function
> >> argument rather than hard code it to 0.
> >>
> > [Alison Wang] I think x3 need to set to 0. Refer to the codes for the
> > warning in kernel,
> >
> > if (boot_args[1] || boot_args[2] || boot_args[3]) {
> > pr_err("WARNING: x1-x3 nonzero in violation of boot
> protocol:\n"
> >
> "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
> > "This indicates a broken bootloader or old
> kernel\n",
> > boot_args[1], boot_args[2], boot_args[3]);
> > }
>
> Yes, that merely means that the kernel doesn't take 3 arguments, it
> takes 4. Today args[1..3] have to be 0, but I don't want to iron that
> out in u-boot code.
>
> So in pseudo-code, what we do today is we call
>
> entry(dt_addr, 0, 0);
>
> and instead we should be calling
>
> entry(dt_addr, 0, 0, 0);
>
> So in U-Boot code that means we should change the prototype for our
> switch function from
>
> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
> u64 entry_point, u64 es_flag);
>
> to
>
> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
> u64 arg4, u64 entry_point, u64 es_flag);
>
> and adapt the macros accordingly to use x5/x6 instead of x4/5.
>
[Alison Wang] I understand your meaning. Actually, I thought that method too. Well, my concern is that there are more changes. Not only armv8_switch_to_el2 and armv8_switch_to_el1, all the places calling them need to change too. It may cause more problems. With this concern, I choose a simple way to fix this issue before.
Best Regards,
Alison Wang
^ permalink raw reply [flat|nested] 9+ messages in thread* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 9:36 ` Alison Wang
@ 2017-01-13 9:55 ` Alexander Graf
2017-01-16 6:31 ` Alison Wang
0 siblings, 1 reply; 9+ messages in thread
From: Alexander Graf @ 2017-01-13 9:55 UTC (permalink / raw)
To: u-boot
On 01/13/2017 10:36 AM, Alison Wang wrote:
>> On 01/13/2017 09:23 AM, Alison Wang wrote:
>>>>> Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
>>>>>
>>>>> For 64-bit kernel, there is a warning about x1-x3 nonzero in
>>>> violation
>>>>> of boot protocol. x3 should be reset to zero before jumping to the
>>>>> kernel.
>>>>>
>>>>> This patch will adjust the parameters to transfer and make sure x3
>>>>> is zero.
>>>>>
>>>>> Signed-off-by: Alison Wang <alison.wang@nxp.com>
>>>> If x3 is part of the boot protocol, please treat it as function
>>>> argument rather than hard code it to 0.
>>>>
>>> [Alison Wang] I think x3 need to set to 0. Refer to the codes for the
>>> warning in kernel,
>>>
>>> if (boot_args[1] || boot_args[2] || boot_args[3]) {
>>> pr_err("WARNING: x1-x3 nonzero in violation of boot
>> protocol:\n"
>> "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
>>> "This indicates a broken bootloader or old
>> kernel\n",
>>> boot_args[1], boot_args[2], boot_args[3]);
>>> }
>> Yes, that merely means that the kernel doesn't take 3 arguments, it
>> takes 4. Today args[1..3] have to be 0, but I don't want to iron that
>> out in u-boot code.
>>
>> So in pseudo-code, what we do today is we call
>>
>> entry(dt_addr, 0, 0);
>>
>> and instead we should be calling
>>
>> entry(dt_addr, 0, 0, 0);
>>
>> So in U-Boot code that means we should change the prototype for our
>> switch function from
>>
>> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
>> u64 entry_point, u64 es_flag);
>>
>> to
>>
>> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
>> u64 arg4, u64 entry_point, u64 es_flag);
>>
>> and adapt the macros accordingly to use x5/x6 instead of x4/5.
>>
> [Alison Wang] I understand your meaning. Actually, I thought that method too. Well, my concern is that there are more changes. Not only armv8_switch_to_el2 and armv8_switch_to_el1, all the places calling them need to change too. It may cause more problems. With this concern, I choose a simple way to fix this issue before.
I think there'll be enough people testing Linux boot :), let's try to
fix it properly right away.
Alex
^ permalink raw reply [flat|nested] 9+ messages in thread* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 9:55 ` Alexander Graf
@ 2017-01-16 6:31 ` Alison Wang
0 siblings, 0 replies; 9+ messages in thread
From: Alison Wang @ 2017-01-16 6:31 UTC (permalink / raw)
To: u-boot
> On 01/13/2017 10:36 AM, Alison Wang wrote:
> >> On 01/13/2017 09:23 AM, Alison Wang wrote:
> >>>>> Am 13.01.2017 um 08:50 schrieb Alison Wang <b18965@freescale.com>:
> >>>>>
> >>>>> For 64-bit kernel, there is a warning about x1-x3 nonzero in
> >>>> violation
> >>>>> of boot protocol. x3 should be reset to zero before jumping to
> the
> >>>>> kernel.
> >>>>>
> >>>>> This patch will adjust the parameters to transfer and make sure
> x3
> >>>>> is zero.
> >>>>>
> >>>>> Signed-off-by: Alison Wang <alison.wang@nxp.com>
> >>>> If x3 is part of the boot protocol, please treat it as function
> >>>> argument rather than hard code it to 0.
> >>>>
> >>> [Alison Wang] I think x3 need to set to 0. Refer to the codes for
> >>> the warning in kernel,
> >>>
> >>> if (boot_args[1] || boot_args[2] || boot_args[3]) {
> >>> pr_err("WARNING: x1-x3 nonzero in violation of
> >>> boot
> >> protocol:\n"
> >> "\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
> >>> "This indicates a broken bootloader or
> old
> >> kernel\n",
> >>> boot_args[1], boot_args[2], boot_args[3]);
> >>> }
> >> Yes, that merely means that the kernel doesn't take 3 arguments, it
> >> takes 4. Today args[1..3] have to be 0, but I don't want to iron
> that
> >> out in u-boot code.
> >>
> >> So in pseudo-code, what we do today is we call
> >>
> >> entry(dt_addr, 0, 0);
> >>
> >> and instead we should be calling
> >>
> >> entry(dt_addr, 0, 0, 0);
> >>
> >> So in U-Boot code that means we should change the prototype for our
> >> switch function from
> >>
> >> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
> >> u64 entry_point, u64 es_flag);
> >>
> >> to
> >>
> >> void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
> >> u64 arg4, u64 entry_point, u64 es_flag);
> >>
> >> and adapt the macros accordingly to use x5/x6 instead of x4/5.
> >>
> > [Alison Wang] I understand your meaning. Actually, I thought that
> method too. Well, my concern is that there are more changes. Not only
> armv8_switch_to_el2 and armv8_switch_to_el1, all the places calling
> them need to change too. It may cause more problems. With this concern,
> I choose a simple way to fix this issue before.
>
> I think there'll be enough people testing Linux boot :), let's try to
> fix it properly right away.
>
[Alison Wang] Ok, I will send v2 patch. Please help to review.
Thanks.
Best Regards,
Alison Wang
^ permalink raw reply [flat|nested] 9+ messages in thread
* [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
2017-01-13 7:50 [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue Alison Wang
2017-01-13 8:11 ` Alexander Graf
@ 2017-01-13 8:16 ` Alison Wang
[not found] ` <CAD0U-hKbBx=cYCCK1Wqd2TQsrC-D92ae0LPbdSk+unm0Y4LvVQ@mail.gmail.com>
1 sibling, 1 reply; 9+ messages in thread
From: Alison Wang @ 2017-01-13 8:16 UTC (permalink / raw)
To: u-boot
Hi, Ryan,
This patch is to fix the issue about a warning for ARMv8 64-bit kernel you reported before. I have tested on my LayerScape boards. Please review and try on your boards too.
Thanks.
Best Regards,
Alison Wang
> -----Original Message-----
> From: Alison Wang [mailto:b18965 at freescale.com]
> Sent: Friday, January 13, 2017 3:50 PM
> To: york sun <york.sun@nxp.com>; ryan.harkin at linaro.org; agraf at suse.de;
> Scott Wood <scott.wood@nxp.com>; Stuart Yoder <stuart.yoder@nxp.com>;
> Leo Li <leoyang.li@nxp.com>; fenghua at phytium.com.cn;
> linus.walleij at linaro.org; u-boot at lists.denx.de
> Cc: Jason Jin <jason.jin@nxp.com>; Alison Wang <alison.wang@nxp.com>
> Subject: [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero
> issue
>
> For 64-bit kernel, there is a warning about x1-x3 nonzero in violation
> of boot protocol. x3 should be reset to zero before jumping to the
> kernel.
>
> This patch will adjust the parameters to transfer and make sure x3 is
> zero.
>
> Signed-off-by: Alison Wang <alison.wang@nxp.com>
> ---
> arch/arm/cpu/armv8/transition.S | 44
> +++++++++++++++++++++++++++++++++++++----
> 1 file changed, 40 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/cpu/armv8/transition.S
> b/arch/arm/cpu/armv8/transition.S index adb9f35..06b6664 100644
> --- a/arch/arm/cpu/armv8/transition.S
> +++ b/arch/arm/cpu/armv8/transition.S
> @@ -26,9 +26,27 @@ ENTRY(armv8_switch_to_el2)
> * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
> * When running in EL2 now, jump to the
> * address saved in x3.
> + *
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4 instead of x3 as parameter.
> */
> - br x3
> -1: armv8_switch_to_el2_m x3, x4, x5
> + mov x4, x3
> + mov x3, #0
> + br x4
> +1:
> + /*
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4, x5, x6 instead of x3, x4,
> + * x5 as parameters.
> + */
> + mov x5, x4
> + mov x4, x3
> + mov x3, #0
> + armv8_switch_to_el2_m x4, x5, x6
> ENDPROC(armv8_switch_to_el2)
>
> ENTRY(armv8_switch_to_el1)
> @@ -36,9 +54,27 @@ ENTRY(armv8_switch_to_el1)
> 0:
> /* x3 is kernel entry point. When running in EL1
> * now, jump to the address saved in x3.
> + *
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4 instead of x3 as parameter.
> + */
> + mov x4, x3
> + mov x3, #0
> + br x4
> +1:
> + /*
> + * For 64-bit kernel, there is a warning about
> + * x1-x3 nonzero in violation of boot protocol.
> + * x3 should be reset to zero before jumping to
> + * the kernel. Use x4, x5, x6 instead of x3, x4,
> + * x5 as parameters.
> */
> - br x3
> -1: armv8_switch_to_el1_m x3, x4, x5
> + mov x5, x4
> + mov x4, x3
> + mov x3, #0
> + armv8_switch_to_el1_m x4, x5, x6
> ENDPROC(armv8_switch_to_el1)
>
> WEAK(armv8_el2_to_aarch32)
> --
> 2.1.0.27.g96db324
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2017-01-16 6:31 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-01-13 7:50 [U-Boot] [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue Alison Wang
2017-01-13 8:11 ` Alexander Graf
2017-01-13 8:23 ` Alison Wang
2017-01-13 8:33 ` Alexander Graf
2017-01-13 9:36 ` Alison Wang
2017-01-13 9:55 ` Alexander Graf
2017-01-16 6:31 ` Alison Wang
2017-01-13 8:16 ` Alison Wang
[not found] ` <CAD0U-hKbBx=cYCCK1Wqd2TQsrC-D92ae0LPbdSk+unm0Y4LvVQ@mail.gmail.com>
[not found] ` <CAD0U-hLZnrfFWdC55s2owGue6yS4uniQXMeQUwaeWMq-g4sP+g@mail.gmail.com>
2017-01-13 8:41 ` Ryan Harkin
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