Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On 31/05/2023 09.13, Thomas Huth wrote:
On 09/05/2023 20.44, Peter Maydell wrote:
On Thu, 13 Apr 2023 at 17:26, Peter Maydell wrote:
On Thu, 13 Apr 2023 at 17:08, Michael Tokarev wrote:
30.03.2023 18:26, Thomas Huth wrote:
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR
registers")
Signed-off-by: Thomas Huth
Has this been forgotten?
Looks like it. Too late for 8.0 now (and it wasn't a regression
since it looks like it was broken in 7.2 as well); will have to
be fixed in 8.1.
Philippe -- looks like this patch still hasn't been queued ?
(It could probably use a Cc: qemu-sta...@nongnu.org at this point.)
It can have my
Reviewed-by: Peter Maydell
*ping*
Philippe, can you please comment? I think this should be good enough at
least for a temporary fix, even if you have more clean ups in this area in
mind later...
Philippe, if you don't mind, I'll take this through my s390x tree since this
fixes a problem on the big-endian s390x hosts.
Thomas
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On 09/05/2023 20.44, Peter Maydell wrote:
On Thu, 13 Apr 2023 at 17:26, Peter Maydell wrote:
On Thu, 13 Apr 2023 at 17:08, Michael Tokarev wrote:
30.03.2023 18:26, Thomas Huth wrote:
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR registers")
Signed-off-by: Thomas Huth
Has this been forgotten?
Looks like it. Too late for 8.0 now (and it wasn't a regression
since it looks like it was broken in 7.2 as well); will have to
be fixed in 8.1.
Philippe -- looks like this patch still hasn't been queued ?
(It could probably use a Cc: qemu-sta...@nongnu.org at this point.)
It can have my
Reviewed-by: Peter Maydell
*ping*
Philippe, can you please comment? I think this should be good enough at
least for a temporary fix, even if you have more clean ups in this area in
mind later...
Thomas
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On Thu, 13 Apr 2023 at 17:26, Peter Maydell wrote:
>
> On Thu, 13 Apr 2023 at 17:08, Michael Tokarev wrote:
> >
> > 30.03.2023 18:26, Thomas Huth wrote:
> > > Booting a Linux kernel with the malta machine is currently broken
> > > on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
> > > for little endian targets only, but uses the wrong way to do this:
> > > cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
> > > it by using the same ways on both, big and little endian hosts.
> > >
> > > Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR
> > > registers")
> > > Signed-off-by: Thomas Huth
> >
> > Has this been forgotten?
>
> Looks like it. Too late for 8.0 now (and it wasn't a regression
> since it looks like it was broken in 7.2 as well); will have to
> be fixed in 8.1.
Philippe -- looks like this patch still hasn't been queued ?
(It could probably use a Cc: qemu-sta...@nongnu.org at this point.)
It can have my
Reviewed-by: Peter Maydell
thanks
-- PMM
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On Thu, 13 Apr 2023 at 17:08, Michael Tokarev wrote:
>
> 30.03.2023 18:26, Thomas Huth wrote:
> > Booting a Linux kernel with the malta machine is currently broken
> > on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
> > for little endian targets only, but uses the wrong way to do this:
> > cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
> > it by using the same ways on both, big and little endian hosts.
> >
> > Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR
> > registers")
> > Signed-off-by: Thomas Huth
>
> Has this been forgotten?
Looks like it. Too late for 8.0 now (and it wasn't a regression
since it looks like it was broken in 7.2 as well); will have to
be fixed in 8.1.
thanks
-- PMM
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
30.03.2023 18:26, Thomas Huth wrote:
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR registers")
Signed-off-by: Thomas Huth
Has this been forgotten?
Thanks,
/mjt
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On 30/03/2023 17.33, Peter Maydell wrote:
On Thu, 30 Mar 2023 at 16:27, Thomas Huth wrote:
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR registers")
Signed-off-by: Thomas Huth
---
I've checked that both, the kernel from
https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mipsel.tgz
and the kernel from
https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mips.tgz
now boot fine on both, a little endian (x86) and a big endian (s390x) host.
hw/mips/malta.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/mips/malta.c b/hw/mips/malta.c
index af9021316d..b26ed1fc9a 100644
--- a/hw/mips/malta.c
+++ b/hw/mips/malta.c
@@ -629,9 +629,9 @@ static void bl_setup_gt64120_jump_kernel(void **p, uint64_t
run_addr,
/* Bus endianess is always reversed */
#if TARGET_BIG_ENDIAN
-#define cpu_to_gt32 cpu_to_le32
+#define cpu_to_gt32(x) (x)
#else
-#define cpu_to_gt32 cpu_to_be32
+#define cpu_to_gt32(x) bswap32(x)
#endif
So if we:
* do nothing to the value on a BE host
* swap the value on an LE host
isn't that the same as cpu_to_be32() in both cases?
No, it's about the *target*, not the host:
* do nothing to the value for a BE *target*
* swap the value for LE *targets*
It's quite weird and it also took me a while to understand this, but this
seems to be the way it's working right with all combinations.
Thomas
Re: [PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
On Thu, 30 Mar 2023 at 16:27, Thomas Huth wrote:
>
> Booting a Linux kernel with the malta machine is currently broken
> on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
> for little endian targets only, but uses the wrong way to do this:
> cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
> it by using the same ways on both, big and little endian hosts.
>
> Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR
> registers")
> Signed-off-by: Thomas Huth
> ---
> I've checked that both, the kernel from
> https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mipsel.tgz
> and the kernel from
> https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mips.tgz
> now boot fine on both, a little endian (x86) and a big endian (s390x) host.
>
> hw/mips/malta.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/hw/mips/malta.c b/hw/mips/malta.c
> index af9021316d..b26ed1fc9a 100644
> --- a/hw/mips/malta.c
> +++ b/hw/mips/malta.c
> @@ -629,9 +629,9 @@ static void bl_setup_gt64120_jump_kernel(void **p,
> uint64_t run_addr,
>
> /* Bus endianess is always reversed */
> #if TARGET_BIG_ENDIAN
> -#define cpu_to_gt32 cpu_to_le32
> +#define cpu_to_gt32(x) (x)
> #else
> -#define cpu_to_gt32 cpu_to_be32
> +#define cpu_to_gt32(x) bswap32(x)
> #endif
So if we:
* do nothing to the value on a BE host
* swap the value on an LE host
isn't that the same as cpu_to_be32() in both cases?
thanks
-- PMM
[PATCH] hw/mips/malta: Fix the malta machine on big endian hosts
Booting a Linux kernel with the malta machine is currently broken
on big endian hosts. The cpu_to_gt32 macro wants to byteswap a value
for little endian targets only, but uses the wrong way to do this:
cpu_to_[lb]e32 works the other way round on big endian hosts! Fix
it by using the same ways on both, big and little endian hosts.
Fixes: 0c8427baf0 ("hw/mips/malta: Use bootloader helper to set BAR registers")
Signed-off-by: Thomas Huth
---
I've checked that both, the kernel from
https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mipsel.tgz
and the kernel from
https://landley.net/toybox/downloads/binaries/mkroot/0.8.9/mips.tgz
now boot fine on both, a little endian (x86) and a big endian (s390x) host.
hw/mips/malta.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/mips/malta.c b/hw/mips/malta.c
index af9021316d..b26ed1fc9a 100644
--- a/hw/mips/malta.c
+++ b/hw/mips/malta.c
@@ -629,9 +629,9 @@ static void bl_setup_gt64120_jump_kernel(void **p, uint64_t
run_addr,
/* Bus endianess is always reversed */
#if TARGET_BIG_ENDIAN
-#define cpu_to_gt32 cpu_to_le32
+#define cpu_to_gt32(x) (x)
#else
-#define cpu_to_gt32 cpu_to_be32
+#define cpu_to_gt32(x) bswap32(x)
#endif
/* setup MEM-to-PCI0 mapping as done by YAMON */
--
2.31.1
