[PATCH v2 0/2] Calculate SDRAM size for Actions OWL SoCs

[PATCH v2 0/2] Calculate SDRAM size for Actions OWL SoCs

[Amit Singh Tomar]

This small series allows us to calculate SDRAM size instead
of guessing it.

Patch (1/2) is re-worked to support S900 SoC along with S700.

These changes have been tested on S700 based Cubieboard7-lite board, and
it would be great if this can be tested on S900. 

Amit Singh Tomar (2):
  Actions: OWL: Calculate SDRAM size
  arm: actions: remove "CONFIG_SYS_SDRAM_SIZE" for Actions Owl Semi SoCs

 arch/arm/mach-owl/soc.c      | 27 ++++++++++++++++++++++++++-
 include/configs/owl-common.h |  1 -
 2 files changed, 26 insertions(+), 2 deletions(-)

-- 
2.7.4

[PATCH v2 1/2] Actions: OWL: Calculate SDRAM size

[Amit Singh Tomar]

Calculate the SDRAM size from DDR capacity register registers instead
of using hard-coded value. This is quite useful to get correct size
on differnt boards based on Actions OWL family of SoCs (S700 and S900).

There is no documentation available that talks about DDR registers, and
this is very much taken from vendor source.

This commit lets Linux boot on Cubieboard7-lite(based on S700).

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* added support for S900
	* updated the commit message to reflect common OWL
	  support.
---
 arch/arm/mach-owl/soc.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-owl/soc.c b/arch/arm/mach-owl/soc.c
index 409cbd319f20..2ae357e3672a 100644
--- a/arch/arm/mach-owl/soc.c
+++ b/arch/arm/mach-owl/soc.c
@@ -13,15 +13,40 @@
 #include <asm/mach-types.h>
 #include <asm/psci.h>
 
+#define DMM_INTERLEAVE_BASE             (0xe0290020)
+#define DMM_INTERLEAVE_PER_CH_CFG       (DMM_INTERLEAVE_BASE +  0x08)
+#define DMM_MASTER_READ_TO              (DMM_INTERLEAVE_BASE +  0x48)
+
 DECLARE_GLOBAL_DATA_PTR;
 
+unsigned int get_owl_ram_size(void)
+{
+	__maybe_unused unsigned int val, cap, channel, channel_num;
+
+	/* ddr capacity register initialized by ddr driver
+	 * in early bootloader
+	 */
+#if defined(CONFIG_MACH_S700)
+	val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0x7;
+	cap =  (val + 1) * 256;
+#elif defined(CONFIG_MACH_S900)
+	chennel_num = (readl(DMM_INTERLEAVE_BASE) >> 24) & 0xf;
+	channel = (ch_num >= 3) ? 1 : 0;
+	val = (readl(DMM_MASTER_READ_TO)) & 0xf;
+	cap = ((val + 1) << channel) * 256;
+#endif
+
+	return cap;
+}
+
 /*
  * dram_init - sets uboots idea of sdram size
  */
 int dram_init(void)
 {
-	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
+	gd->ram_size = get_owl_ram_size() * 1024 * 1024;
 	return 0;
+
 }
 
 /* This is called after dram_init() so use get_ram_size result */
-- 
2.7.4

[PATCH v2 1/2] Actions: OWL: Calculate SDRAM size

[Manivannan Sadhasivam]

Hi Amit,

On Fri, May 08, 2020 at 03:53:45PM +0530, Amit Singh Tomar wrote:
> Calculate the SDRAM size from DDR capacity register registers instead
> of using hard-coded value. This is quite useful to get correct size
> on differnt boards based on Actions OWL family of SoCs (S700 and S900).
> 
> There is no documentation available that talks about DDR registers, and
> this is very much taken from vendor source.
> 
> This commit lets Linux boot on Cubieboard7-lite(based on S700).
> 
> Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> ---
> Changes since v1:
> 	* added support for S900
> 	* updated the commit message to reflect common OWL
> 	  support.
> ---
>  arch/arm/mach-owl/soc.c | 27 ++++++++++++++++++++++++++-
>  1 file changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-owl/soc.c b/arch/arm/mach-owl/soc.c
> index 409cbd319f20..2ae357e3672a 100644
> --- a/arch/arm/mach-owl/soc.c
> +++ b/arch/arm/mach-owl/soc.c
> @@ -13,15 +13,40 @@
>  #include <asm/mach-types.h>
>  #include <asm/psci.h>
>  
> +#define DMM_INTERLEAVE_BASE             (0xe0290020)
> +#define DMM_INTERLEAVE_PER_CH_CFG       (DMM_INTERLEAVE_BASE +  0x08)
> +#define DMM_MASTER_READ_TO              (DMM_INTERLEAVE_BASE +  0x48)
> +
>  DECLARE_GLOBAL_DATA_PTR;
>  
> +unsigned int get_owl_ram_size(void)
> +{
> +	__maybe_unused unsigned int val, cap, channel, channel_num;
> +
> +	/* ddr capacity register initialized by ddr driver
> +	 * in early bootloader
> +	 */
> +#if defined(CONFIG_MACH_S700)
> +	val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0x7;
> +	cap =  (val + 1) * 256;
> +#elif defined(CONFIG_MACH_S900)
> +	chennel_num = (readl(DMM_INTERLEAVE_BASE) >> 24) & 0xf;
> +	channel = (ch_num >= 3) ? 1 : 0;
> +	val = (readl(DMM_MASTER_READ_TO)) & 0xf;
> +	cap = ((val + 1) << channel) * 256;

This doesn't work on Bubblegum96. But poking into the vendor tree, I'm able
to come up with below working code:

        val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0xf;
        cap =  64 * (1 << val);

So, you can use this and remove other stuffs. Also this function should be named
as owl_get_ddr_cap().

Thanks,
Mani

> +#endif
> +
> +	return cap;
> +}
> +
>  /*
>   * dram_init - sets uboots idea of sdram size
>   */
>  int dram_init(void)
>  {
> -	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
> +	gd->ram_size = get_owl_ram_size() * 1024 * 1024;
>  	return 0;
> +
>  }
>  
>  /* This is called after dram_init() so use get_ram_size result */
> -- 
> 2.7.4
> 

[PATCH v2 1/2] Actions: OWL: Calculate SDRAM size

[Amit Tomer]

Hi Mani,
>
> This doesn't work on Bubblegum96. But poking into the vendor tree, I'm able
> to come up with below working code:
>
>         val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0xf;
>         cap =  64 * (1 << val);
>
> So, you can use this and remove other stuffs. Also this function should be named
> as owl_get_ddr_cap().

Thanks for pointing this out, and I just sent v3 as v2 didn't even
compile for Bubblegum96.

Would send the updated version that works on S900.

Thanks
Amit.

[PATCH v2 2/2] arm: actions: remove "CONFIG_SYS_SDRAM_SIZE" for Actions Owl Semi SoCs

[Amit Singh Tomar]

Now that, we calculate SDRAM size by reading DDR registers,
"CONFIG_SYS_SDRAM_SIZE" is no more needed.

This commit removes "CONFIG_SYS_SDRAM_SIZE" from common configuration
file.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
 include/configs/owl-common.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/include/configs/owl-common.h b/include/configs/owl-common.h
index f77a5fa4c114..7634578f856d 100644
--- a/include/configs/owl-common.h
+++ b/include/configs/owl-common.h
@@ -12,7 +12,6 @@
 
 /* SDRAM Definitions */
 #define CONFIG_SYS_SDRAM_BASE		0x0
-#define CONFIG_SYS_SDRAM_SIZE		0x80000000
 
 /* Generic Timer Definitions */
 #define COUNTER_FREQUENCY		(24000000)	/* 24MHz */
-- 
2.7.4