[4/4] sunxi: move arch timer setup out of board/ directory

At the moment we have an #ifdef-protected routine in
board/sunxi/board.c, which sets up the arch timer CNTFRQ register, if
that hasn't been done already.
This only applies to ARMv7 SoCs running in secure state, and so is
much better located in the arch/arm/mach-sunxi directory.

Move that routine into a separate function and file in said directory,
which also allows to trigger the compilation for ARMv7 in the Makefile.
Also move the call to it into the arch/arm version of board.c.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 arch/arm/mach-sunxi/Makefile     |  4 ++++
 arch/arm/mach-sunxi/arch_timer.c | 39 ++++++++++++++++++++++++++++++++
 arch/arm/mach-sunxi/board.c      | 14 ++++++++----
 board/sunxi/board.c              | 34 +---------------------------
 4 files changed, 54 insertions(+), 37 deletions(-)
 create mode 100644 arch/arm/mach-sunxi/arch_timer.c

Hi Andre,

On 12/13/22 18:22, Andre Przywara wrote:
> At the moment we have an #ifdef-protected routine in
> board/sunxi/board.c, which sets up the arch timer CNTFRQ register, if
> that hasn't been done already.
> This only applies to ARMv7 SoCs running in secure state, and so is
> much better located in the arch/arm/mach-sunxi directory.
> 
> Move that routine into a separate function and file in said directory,
> which also allows to trigger the compilation for ARMv7 in the Makefile.
> Also move the call to it into the arch/arm version of board.c.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
>  arch/arm/mach-sunxi/Makefile     |  4 ++++
>  arch/arm/mach-sunxi/arch_timer.c | 39 ++++++++++++++++++++++++++++++++
>  arch/arm/mach-sunxi/board.c      | 14 ++++++++----
>  board/sunxi/board.c              | 34 +---------------------------
>  4 files changed, 54 insertions(+), 37 deletions(-)
>  create mode 100644 arch/arm/mach-sunxi/arch_timer.c
> 
> diff --git a/arch/arm/mach-sunxi/Makefile b/arch/arm/mach-sunxi/Makefile
> index 58f807cb82d..335c44476e9 100644
> --- a/arch/arm/mach-sunxi/Makefile
> +++ b/arch/arm/mach-sunxi/Makefile
> @@ -26,8 +26,12 @@ obj-$(CONFIG_MACH_SUN8I)	+= clock_sun6i.o
>  endif
>  obj-$(CONFIG_MACH_SUN9I)	+= clock_sun9i.o gtbus_sun9i.o
>  obj-$(CONFIG_SUN50I_GEN_H6)	+= clock_sun50i_h6.o
> +
>  ifndef CONFIG_ARM64
>  obj-y	+= timer.o
> +ifndef CONFIG_MACH_SUNIV

Probably Allwinner will not release any new ARMv5 SoC, but would it be
more future-proof (and a bit more meaningful) to condition this on
CONFIG_CPU_V7A?

Alternatively, would it make sense to put this code inside
arch/arm/cpu/armv7/arch_timer.c? I don't know why we wouldn't want to
enable CONFIG_SYS_ARCH_TIMER on sunxi SoCs where it is available. And
making this generic could eventually remove the need for the version in
arch/arm/cpu/armv7/nonsec_virt.S. But this patch is still an improvement
as-is.

Tested-by: Samuel Holland <samuel@sholland.org>

> +obj-y	+= arch_timer.o
> +endif
>  endif
>  
>  ifdef CONFIG_SPL_BUILD
> diff --git a/arch/arm/mach-sunxi/arch_timer.c b/arch/arm/mach-sunxi/arch_timer.c
> new file mode 100644
> index 00000000000..c0e4310741f
> --- /dev/null
> +++ b/arch/arm/mach-sunxi/arch_timer.c
> @@ -0,0 +1,39 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * ARM Generic Timer CNTFRQ setup
> + *
> + * (C) Copyright 2013 Oliver Schinagl <oliver@schinagl.nl>

`git blame` points to cba69eeeaa67d3fb93ec6f3abab1f653abf895a9 and
d96ebc468d0dff6eb6f069bba03b3f0e33aa22de as the source for this code, so
this authorship is incorrect.

> + */
> +
> +#include <stdint.h>

This does not do what you expect, or really anything at all. The comment
there suggests using linux/types.h.

Regards,
Samuel

> +#include <log.h>
> +#include <asm/armv7.h>
> +
> +void setup_arch_timer(void)
> +{
> +	uint32_t id_pfr1, freq;
> +
> +	asm volatile("mrc p15, 0, %0, c0, c1, 1" : "=r"(id_pfr1));
> +	debug("id_pfr1: 0x%08x\n", id_pfr1);
> +	/* Generic Timer Extension available? */
> +	if (((id_pfr1 >> CPUID_ARM_GENTIMER_SHIFT) & 0xf) == 0)
> +		return;
> +
> +	/*
> +	 * CNTFRQ is a secure register, so we will crash if we try to
> +	 * write this from the non-secure world (read is OK, though).
> +	 * In case some bootcode has already set the correct value,
> +	 * we avoid the risk of writing to it.
> +	 */
> +	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r"(freq));
> +	if (freq == CONFIG_COUNTER_FREQUENCY)
> +		return;
> +
> +	debug("arch timer frequency is %d Hz, should be %d, fixing ...\n",
> +	      freq, CONFIG_COUNTER_FREQUENCY);
> +	if (IS_ENABLED(CONFIG_NON_SECURE))
> +		printf("arch timer frequency is wrong, but cannot adjust it\n");
> +	else
> +		asm volatile("mcr p15, 0, %0, c14, c0, 0"
> +			     : : "r"(CONFIG_COUNTER_FREQUENCY));
> +}
> diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
> index 0c4b6dd1ca3..943f89eaa78 100644
> --- a/arch/arm/mach-sunxi/board.c
> +++ b/arch/arm/mach-sunxi/board.c
> @@ -347,10 +347,6 @@ u32 spl_boot_device(void)
>  	return sunxi_get_boot_device();
>  }
>  
> -__weak void sunxi_sram_init(void)
> -{
> -}
> -
>  /*
>   * When booting from an eMMC boot partition, the SPL puts the same boot
>   * source code into SRAM A1 as when loading the SPL from the normal
> @@ -434,10 +430,20 @@ u32 spl_mmc_boot_mode(struct mmc *mmc, const u32 boot_device)
>  	return result;
>  }
>  
> +__weak void sunxi_sram_init(void)
> +{
> +}
> +
> +__weak void setup_arch_timer(void)
> +{
> +}
> +
>  void board_init_f(ulong dummy)
>  {
>  	sunxi_sram_init();
>  
> +	setup_arch_timer();
> +
>  #if defined CONFIG_MACH_SUN6I || defined CONFIG_MACH_SUN8I_H3
>  	/* Enable non-secure access to some peripherals */
>  	tzpc_init();
> diff --git a/board/sunxi/board.c b/board/sunxi/board.c
> index 827e545032e..55501fafc38 100644
> --- a/board/sunxi/board.c
> +++ b/board/sunxi/board.c
> @@ -34,9 +34,6 @@
>  #include <asm/global_data.h>
>  #include <linux/delay.h>
>  #include <u-boot/crc.h>
> -#ifndef CONFIG_ARM64
> -#include <asm/armv7.h>
> -#endif
>  #include <asm/gpio.h>
>  #include <asm/io.h>
>  #include <u-boot/crc.h>
> @@ -187,39 +184,10 @@ enum env_location env_get_location(enum env_operation op, int prio)
>  /* add board specific code here */
>  int board_init(void)
>  {
> -	__maybe_unused int id_pfr1, ret, satapwr_pin, macpwr_pin;
> +	int ret, satapwr_pin, macpwr_pin;
>  
>  	gd->bd->bi_boot_params = (PHYS_SDRAM_0 + 0x100);
>  
> -#if !defined(CONFIG_ARM64) && !defined(CONFIG_MACH_SUNIV)
> -	asm volatile("mrc p15, 0, %0, c0, c1, 1" : "=r"(id_pfr1));
> -	debug("id_pfr1: 0x%08x\n", id_pfr1);
> -	/* Generic Timer Extension available? */
> -	if ((id_pfr1 >> CPUID_ARM_GENTIMER_SHIFT) & 0xf) {
> -		uint32_t freq;
> -
> -		debug("Setting CNTFRQ\n");
> -
> -		/*
> -		 * CNTFRQ is a secure register, so we will crash if we try to
> -		 * write this from the non-secure world (read is OK, though).
> -		 * In case some bootcode has already set the correct value,
> -		 * we avoid the risk of writing to it.
> -		 */
> -		asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r"(freq));
> -		if (freq != CONFIG_COUNTER_FREQUENCY) {
> -			debug("arch timer frequency is %d Hz, should be %d, fixing ...\n",
> -			      freq, CONFIG_COUNTER_FREQUENCY);
> -#ifdef CONFIG_NON_SECURE
> -			printf("arch timer frequency is wrong, but cannot adjust it\n");
> -#else
> -			asm volatile("mcr p15, 0, %0, c14, c0, 0"
> -				     : : "r"(CONFIG_COUNTER_FREQUENCY));
> -#endif
> -		}
> -	}
> -#endif /* !CONFIG_ARM64 && !CONFIG_MACH_SUNIV */
> -
>  	ret = axp_gpio_init();
>  	if (ret)
>  		return ret;

On Wed, 14 Dec 2022 00:14:49 -0600
Samuel Holland <samuel@sholland.org> wrote:

Hi Samuel,

thanks for having a look!

> On 12/13/22 18:22, Andre Przywara wrote:
> > At the moment we have an #ifdef-protected routine in
> > board/sunxi/board.c, which sets up the arch timer CNTFRQ register, if
> > that hasn't been done already.
> > This only applies to ARMv7 SoCs running in secure state, and so is
> > much better located in the arch/arm/mach-sunxi directory.
> > 
> > Move that routine into a separate function and file in said directory,
> > which also allows to trigger the compilation for ARMv7 in the Makefile.
> > Also move the call to it into the arch/arm version of board.c.
> > 
> > Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> > ---
> >  arch/arm/mach-sunxi/Makefile     |  4 ++++
> >  arch/arm/mach-sunxi/arch_timer.c | 39 ++++++++++++++++++++++++++++++++
> >  arch/arm/mach-sunxi/board.c      | 14 ++++++++----
> >  board/sunxi/board.c              | 34 +---------------------------
> >  4 files changed, 54 insertions(+), 37 deletions(-)
> >  create mode 100644 arch/arm/mach-sunxi/arch_timer.c
> > 
> > diff --git a/arch/arm/mach-sunxi/Makefile b/arch/arm/mach-sunxi/Makefile
> > index 58f807cb82d..335c44476e9 100644
> > --- a/arch/arm/mach-sunxi/Makefile
> > +++ b/arch/arm/mach-sunxi/Makefile
> > @@ -26,8 +26,12 @@ obj-$(CONFIG_MACH_SUN8I)	+= clock_sun6i.o
> >  endif
> >  obj-$(CONFIG_MACH_SUN9I)	+= clock_sun9i.o gtbus_sun9i.o
> >  obj-$(CONFIG_SUN50I_GEN_H6)	+= clock_sun50i_h6.o
> > +
> >  ifndef CONFIG_ARM64
> >  obj-y	+= timer.o
> > +ifndef CONFIG_MACH_SUNIV  
> 
> Probably Allwinner will not release any new ARMv5 SoC, but would it be
> more future-proof (and a bit more meaningful) to condition this on
> CONFIG_CPU_V7A?

Ah, of course, I forgot about that symbol, and just saw !CONFIG_ARM64.

> Alternatively, would it make sense to put this code inside
> arch/arm/cpu/armv7/arch_timer.c? I don't know why we wouldn't want to
> enable CONFIG_SYS_ARCH_TIMER on sunxi SoCs where it is available. And
> making this generic could eventually remove the need for the version in
> arch/arm/cpu/armv7/nonsec_virt.S. But this patch is still an improvement
> as-is.

Yeah, that indeed sounds even better, I will give it a try. I guess
sunxi will stay the only user for now, but we can extend this later on.

Thanks for the suggestion!

Cheers,
Andre

> Tested-by: Samuel Holland <samuel@sholland.org>
> 
> > +obj-y	+= arch_timer.o
> > +endif
> >  endif
> >  
> >  ifdef CONFIG_SPL_BUILD
> > diff --git a/arch/arm/mach-sunxi/arch_timer.c b/arch/arm/mach-sunxi/arch_timer.c
> > new file mode 100644
> > index 00000000000..c0e4310741f
> > --- /dev/null
> > +++ b/arch/arm/mach-sunxi/arch_timer.c
> > @@ -0,0 +1,39 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * ARM Generic Timer CNTFRQ setup
> > + *
> > + * (C) Copyright 2013 Oliver Schinagl <oliver@schinagl.nl>  
> 
> `git blame` points to cba69eeeaa67d3fb93ec6f3abab1f653abf895a9 and
> d96ebc468d0dff6eb6f069bba03b3f0e33aa22de as the source for this code, so
> this authorship is incorrect.
> 
> > + */
> > +
> > +#include <stdint.h>  
> 
> This does not do what you expect, or really anything at all. The comment
> there suggests using linux/types.h.
> 
> Regards,
> Samuel
> 
> > +#include <log.h>
> > +#include <asm/armv7.h>
> > +
> > +void setup_arch_timer(void)
> > +{
> > +	uint32_t id_pfr1, freq;
> > +
> > +	asm volatile("mrc p15, 0, %0, c0, c1, 1" : "=r"(id_pfr1));
> > +	debug("id_pfr1: 0x%08x\n", id_pfr1);
> > +	/* Generic Timer Extension available? */
> > +	if (((id_pfr1 >> CPUID_ARM_GENTIMER_SHIFT) & 0xf) == 0)
> > +		return;
> > +
> > +	/*
> > +	 * CNTFRQ is a secure register, so we will crash if we try to
> > +	 * write this from the non-secure world (read is OK, though).
> > +	 * In case some bootcode has already set the correct value,
> > +	 * we avoid the risk of writing to it.
> > +	 */
> > +	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r"(freq));
> > +	if (freq == CONFIG_COUNTER_FREQUENCY)
> > +		return;
> > +
> > +	debug("arch timer frequency is %d Hz, should be %d, fixing ...\n",
> > +	      freq, CONFIG_COUNTER_FREQUENCY);
> > +	if (IS_ENABLED(CONFIG_NON_SECURE))
> > +		printf("arch timer frequency is wrong, but cannot adjust it\n");
> > +	else
> > +		asm volatile("mcr p15, 0, %0, c14, c0, 0"
> > +			     : : "r"(CONFIG_COUNTER_FREQUENCY));
> > +}
> > diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
> > index 0c4b6dd1ca3..943f89eaa78 100644
> > --- a/arch/arm/mach-sunxi/board.c
> > +++ b/arch/arm/mach-sunxi/board.c
> > @@ -347,10 +347,6 @@ u32 spl_boot_device(void)
> >  	return sunxi_get_boot_device();
> >  }
> >  
> > -__weak void sunxi_sram_init(void)
> > -{
> > -}
> > -
> >  /*
> >   * When booting from an eMMC boot partition, the SPL puts the same boot
> >   * source code into SRAM A1 as when loading the SPL from the normal
> > @@ -434,10 +430,20 @@ u32 spl_mmc_boot_mode(struct mmc *mmc, const u32 boot_device)
> >  	return result;
> >  }
> >  
> > +__weak void sunxi_sram_init(void)
> > +{
> > +}
> > +
> > +__weak void setup_arch_timer(void)
> > +{
> > +}
> > +
> >  void board_init_f(ulong dummy)
> >  {
> >  	sunxi_sram_init();
> >  
> > +	setup_arch_timer();
> > +
> >  #if defined CONFIG_MACH_SUN6I || defined CONFIG_MACH_SUN8I_H3
> >  	/* Enable non-secure access to some peripherals */
> >  	tzpc_init();
> > diff --git a/board/sunxi/board.c b/board/sunxi/board.c
> > index 827e545032e..55501fafc38 100644
> > --- a/board/sunxi/board.c
> > +++ b/board/sunxi/board.c
> > @@ -34,9 +34,6 @@
> >  #include <asm/global_data.h>
> >  #include <linux/delay.h>
> >  #include <u-boot/crc.h>
> > -#ifndef CONFIG_ARM64
> > -#include <asm/armv7.h>
> > -#endif
> >  #include <asm/gpio.h>
> >  #include <asm/io.h>
> >  #include <u-boot/crc.h>
> > @@ -187,39 +184,10 @@ enum env_location env_get_location(enum env_operation op, int prio)
> >  /* add board specific code here */
> >  int board_init(void)
> >  {
> > -	__maybe_unused int id_pfr1, ret, satapwr_pin, macpwr_pin;
> > +	int ret, satapwr_pin, macpwr_pin;
> >  
> >  	gd->bd->bi_boot_params = (PHYS_SDRAM_0 + 0x100);
> >  
> > -#if !defined(CONFIG_ARM64) && !defined(CONFIG_MACH_SUNIV)
> > -	asm volatile("mrc p15, 0, %0, c0, c1, 1" : "=r"(id_pfr1));
> > -	debug("id_pfr1: 0x%08x\n", id_pfr1);
> > -	/* Generic Timer Extension available? */
> > -	if ((id_pfr1 >> CPUID_ARM_GENTIMER_SHIFT) & 0xf) {
> > -		uint32_t freq;
> > -
> > -		debug("Setting CNTFRQ\n");
> > -
> > -		/*
> > -		 * CNTFRQ is a secure register, so we will crash if we try to
> > -		 * write this from the non-secure world (read is OK, though).
> > -		 * In case some bootcode has already set the correct value,
> > -		 * we avoid the risk of writing to it.
> > -		 */
> > -		asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r"(freq));
> > -		if (freq != CONFIG_COUNTER_FREQUENCY) {
> > -			debug("arch timer frequency is %d Hz, should be %d, fixing ...\n",
> > -			      freq, CONFIG_COUNTER_FREQUENCY);
> > -#ifdef CONFIG_NON_SECURE
> > -			printf("arch timer frequency is wrong, but cannot adjust it\n");
> > -#else
> > -			asm volatile("mcr p15, 0, %0, c14, c0, 0"
> > -				     : : "r"(CONFIG_COUNTER_FREQUENCY));
> > -#endif
> > -		}
> > -	}
> > -#endif /* !CONFIG_ARM64 && !CONFIG_MACH_SUNIV */
> > -
> >  	ret = axp_gpio_init();
> >  	if (ret)
> >  		return ret;  
>