* Re: [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability
2020-11-30 8:57 [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability Geert Uytterhoeven
@ 2020-11-30 21:57 ` Stephen Rothwell
2020-12-01 10:03 ` Stephen Rothwell
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Stephen Rothwell @ 2020-11-30 21:57 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Stephen Boyd, Michael Turquette, linux-kernel, Gareth Williams,
linux-renesas-soc, Paul Mackerras, linuxppc-dev, linux-clk
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Hi Geert,
On Mon, 30 Nov 2020 09:57:43 +0100 Geert Uytterhoeven <geert+renesas@glider.be> wrote:
>
> The R9A06G032 clock driver uses an array of packed structures to reduce
> kernel size. However, this array contains pointers, which are no longer
> aligned naturally, and cannot be relocated on PPC64. Hence when
> compile-testing this driver on PPC64 with CONFIG_RELOCATABLE=y (e.g.
> PowerPC allyesconfig), the following warnings are produced:
>
> WARNING: 136 bad relocations
> c000000000616be3 R_PPC64_UADDR64 .rodata+0x00000000000cf338
> c000000000616bfe R_PPC64_UADDR64 .rodata+0x00000000000cf370
> ...
>
> Fix this by dropping the __packed attribute from the r9a06g032_clkdesc
> definition, trading a small size increase for portability.
>
> This increases the 156-entry clock table by 1 byte per entry, but due to
> the compiler generating more efficient code for unpacked accesses, the
> net size increase is only 76 bytes (gcc 9.3.0 on arm32).
>
> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> Fixes: 4c3d88526eba2143 ("clk: renesas: Renesas R9A06G032 clock driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> v2:
> - Fix authorship.
> ---
> drivers/clk/renesas/r9a06g032-clocks.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Thanks.
I have added that to my fixes tree until it gets picked up elsewhere.
--
Cheers,
Stephen Rothwell
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability
2020-11-30 8:57 [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability Geert Uytterhoeven
2020-11-30 21:57 ` Stephen Rothwell
@ 2020-12-01 10:03 ` Stephen Rothwell
2020-12-05 6:24 ` Stephen Boyd
2020-12-07 21:58 ` Stephen Boyd
3 siblings, 0 replies; 6+ messages in thread
From: Stephen Rothwell @ 2020-12-01 10:03 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Stephen Boyd, Michael Turquette, linux-kernel, Gareth Williams,
linux-renesas-soc, Paul Mackerras, linuxppc-dev, linux-clk
[-- Attachment #1: Type: text/plain, Size: 1969 bytes --]
Hi Geert,
On Mon, 30 Nov 2020 09:57:43 +0100 Geert Uytterhoeven <geert+renesas@glider.be> wrote:
>
> The R9A06G032 clock driver uses an array of packed structures to reduce
> kernel size. However, this array contains pointers, which are no longer
> aligned naturally, and cannot be relocated on PPC64. Hence when
> compile-testing this driver on PPC64 with CONFIG_RELOCATABLE=y (e.g.
> PowerPC allyesconfig), the following warnings are produced:
>
> WARNING: 136 bad relocations
> c000000000616be3 R_PPC64_UADDR64 .rodata+0x00000000000cf338
> c000000000616bfe R_PPC64_UADDR64 .rodata+0x00000000000cf370
> ...
>
> Fix this by dropping the __packed attribute from the r9a06g032_clkdesc
> definition, trading a small size increase for portability.
>
> This increases the 156-entry clock table by 1 byte per entry, but due to
> the compiler generating more efficient code for unpacked accesses, the
> net size increase is only 76 bytes (gcc 9.3.0 on arm32).
>
> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> Fixes: 4c3d88526eba2143 ("clk: renesas: Renesas R9A06G032 clock driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> v2:
> - Fix authorship.
> ---
> drivers/clk/renesas/r9a06g032-clocks.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/renesas/r9a06g032-clocks.c b/drivers/clk/renesas/r9a06g032-clocks.c
> index d900f6bf53d0b944..892e91b92f2c80f5 100644
> --- a/drivers/clk/renesas/r9a06g032-clocks.c
> +++ b/drivers/clk/renesas/r9a06g032-clocks.c
> @@ -55,7 +55,7 @@ struct r9a06g032_clkdesc {
> u16 sel, g1, r1, g2, r2;
> } dual;
> };
> -} __packed;
> +};
>
> #define I_GATE(_clk, _rst, _rdy, _midle, _scon, _mirack, _mistat) \
> { .gate = _clk, .reset = _rst, \
> --
> 2.25.1
>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> # PowerPC allyesconfig build
--
Cheers,
Stephen Rothwell
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability
2020-11-30 8:57 [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability Geert Uytterhoeven
2020-11-30 21:57 ` Stephen Rothwell
2020-12-01 10:03 ` Stephen Rothwell
@ 2020-12-05 6:24 ` Stephen Boyd
2020-12-05 9:05 ` Geert Uytterhoeven
2020-12-07 21:58 ` Stephen Boyd
3 siblings, 1 reply; 6+ messages in thread
From: Stephen Boyd @ 2020-12-05 6:24 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Geert Uytterhoeven, Michael Ellerman,
Michael Turquette, Paul Mackerras, Stephen Rothwell
Cc: Geert Uytterhoeven, linux-kernel, Gareth Williams,
linux-renesas-soc, linuxppc-dev, linux-clk
Quoting Geert Uytterhoeven (2020-11-30 00:57:43)
> The R9A06G032 clock driver uses an array of packed structures to reduce
> kernel size. However, this array contains pointers, which are no longer
> aligned naturally, and cannot be relocated on PPC64. Hence when
> compile-testing this driver on PPC64 with CONFIG_RELOCATABLE=y (e.g.
> PowerPC allyesconfig), the following warnings are produced:
>
> WARNING: 136 bad relocations
> c000000000616be3 R_PPC64_UADDR64 .rodata+0x00000000000cf338
> c000000000616bfe R_PPC64_UADDR64 .rodata+0x00000000000cf370
> ...
>
> Fix this by dropping the __packed attribute from the r9a06g032_clkdesc
> definition, trading a small size increase for portability.
>
> This increases the 156-entry clock table by 1 byte per entry, but due to
> the compiler generating more efficient code for unpacked accesses, the
> net size increase is only 76 bytes (gcc 9.3.0 on arm32).
>
> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> Fixes: 4c3d88526eba2143 ("clk: renesas: Renesas R9A06G032 clock driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
Acked-by: Stephen Boyd <sboyd@kernel.org>
Unless you want me to pick this up for clk-fixes?
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability
2020-12-05 6:24 ` Stephen Boyd
@ 2020-12-05 9:05 ` Geert Uytterhoeven
0 siblings, 0 replies; 6+ messages in thread
From: Geert Uytterhoeven @ 2020-12-05 9:05 UTC (permalink / raw)
To: Stephen Boyd
Cc: Stephen Rothwell, Geert Uytterhoeven, Michael Turquette,
Linux Kernel Mailing List, Gareth Williams, Linux-Renesas,
Paul Mackerras, linuxppc-dev, linux-clk
Hi Stephen,
On Sat, Dec 5, 2020 at 7:24 AM Stephen Boyd <sboyd@kernel.org> wrote:
> Quoting Geert Uytterhoeven (2020-11-30 00:57:43)
> > The R9A06G032 clock driver uses an array of packed structures to reduce
> > kernel size. However, this array contains pointers, which are no longer
> > aligned naturally, and cannot be relocated on PPC64. Hence when
> > compile-testing this driver on PPC64 with CONFIG_RELOCATABLE=y (e.g.
> > PowerPC allyesconfig), the following warnings are produced:
> >
> > WARNING: 136 bad relocations
> > c000000000616be3 R_PPC64_UADDR64 .rodata+0x00000000000cf338
> > c000000000616bfe R_PPC64_UADDR64 .rodata+0x00000000000cf370
> > ...
> >
> > Fix this by dropping the __packed attribute from the r9a06g032_clkdesc
> > definition, trading a small size increase for portability.
> >
> > This increases the 156-entry clock table by 1 byte per entry, but due to
> > the compiler generating more efficient code for unpacked accesses, the
> > net size increase is only 76 bytes (gcc 9.3.0 on arm32).
> >
> > Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> > Fixes: 4c3d88526eba2143 ("clk: renesas: Renesas R9A06G032 clock driver")
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
>
> Acked-by: Stephen Boyd <sboyd@kernel.org>
>
> Unless you want me to pick this up for clk-fixes?
Yes please. Forgot to retain this comment for v2:
"Please take directly (ppc or clk), as this is a build fix.
https://lore.kernel.org/linux-clk/20201128122819.32187696@canb.auug.org.au/"
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability
2020-11-30 8:57 [PATCH v2] clk: renesas: r9a06g032: Drop __packed for portability Geert Uytterhoeven
` (2 preceding siblings ...)
2020-12-05 6:24 ` Stephen Boyd
@ 2020-12-07 21:58 ` Stephen Boyd
3 siblings, 0 replies; 6+ messages in thread
From: Stephen Boyd @ 2020-12-07 21:58 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Geert Uytterhoeven, Michael Ellerman,
Michael Turquette, Paul Mackerras, Stephen Rothwell
Cc: Geert Uytterhoeven, linux-kernel, Gareth Williams,
linux-renesas-soc, linuxppc-dev, linux-clk
Quoting Geert Uytterhoeven (2020-11-30 00:57:43)
> The R9A06G032 clock driver uses an array of packed structures to reduce
> kernel size. However, this array contains pointers, which are no longer
> aligned naturally, and cannot be relocated on PPC64. Hence when
> compile-testing this driver on PPC64 with CONFIG_RELOCATABLE=y (e.g.
> PowerPC allyesconfig), the following warnings are produced:
>
> WARNING: 136 bad relocations
> c000000000616be3 R_PPC64_UADDR64 .rodata+0x00000000000cf338
> c000000000616bfe R_PPC64_UADDR64 .rodata+0x00000000000cf370
> ...
>
> Fix this by dropping the __packed attribute from the r9a06g032_clkdesc
> definition, trading a small size increase for portability.
>
> This increases the 156-entry clock table by 1 byte per entry, but due to
> the compiler generating more efficient code for unpacked accesses, the
> net size increase is only 76 bytes (gcc 9.3.0 on arm32).
>
> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> Fixes: 4c3d88526eba2143 ("clk: renesas: Renesas R9A06G032 clock driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
Applied to clk-fixes
^ permalink raw reply [flat|nested] 6+ messages in thread