[PATCH 1/3] ARM: OMAP4+: hwmod data: Don't prevent RESET of USB Host module

Paul Walmsley paul at pwsan.com
Sun Dec 8 20:26:15 EST 2013


Hi Benoît,

On Tue, 3 Dec 2013, Roger Quadros wrote:

> Without this, the USB devices are sometimes not detected on OMAP4 Panda
> with u-boot v2013.10.
> 
> Unlike what the comment states, errata i660 does not state that we
> can't RESET the USB host module. Instead it states that RESET is the
> only way to recover from a deadlock situation.
> 
> RESET ensures that the module is in a known good state irrespective
> of what bootloader does with the module, so it must be done at boot.
> 
> Reported-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> Signed-off-by: Roger Quadros <rogerq at ti.com>

Acked-by: Paul Walmsley <paul at pwsan.com>

Will you pick this up for the -rc series, or do you want me or Tony to?  
Roger writes that this one's pretty important.


- Paul


> ---
>  arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 12 ++----------
>  arch/arm/mach-omap2/omap_hwmod_54xx_data.c | 13 +++----------
>  2 files changed, 5 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
> index 1e5b12c..3318cae9 100644
> --- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
> +++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
> @@ -2937,7 +2937,7 @@ static struct omap_hwmod_class_sysconfig omap44xx_usb_host_hs_sysc = {
>  	.sysc_offs	= 0x0010,
>  	.syss_offs	= 0x0014,
>  	.sysc_flags	= (SYSC_HAS_MIDLEMODE | SYSC_HAS_SIDLEMODE |
> -			   SYSC_HAS_SOFTRESET),
> +			   SYSC_HAS_SOFTRESET | SYSC_HAS_RESET_STATUS),
>  	.idlemodes	= (SIDLE_FORCE | SIDLE_NO | SIDLE_SMART |
>  			   SIDLE_SMART_WKUP | MSTANDBY_FORCE | MSTANDBY_NO |
>  			   MSTANDBY_SMART | MSTANDBY_SMART_WKUP),
> @@ -3001,15 +3001,7 @@ static struct omap_hwmod omap44xx_usb_host_hs_hwmod = {
>  	 * hence HWMOD_SWSUP_MSTANDBY
>  	 */
>  
> -	/*
> -	 * During system boot; If the hwmod framework resets the module
> -	 * the module will have smart idle settings; which can lead to deadlock
> -	 * (above Errata Id:i660); so, dont reset the module during boot;
> -	 * Use HWMOD_INIT_NO_RESET.
> -	 */
> -
> -	.flags		= HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY |
> -			  HWMOD_INIT_NO_RESET,
> +	.flags		= HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY,
>  };
>  
>  /*
> diff --git a/arch/arm/mach-omap2/omap_hwmod_54xx_data.c b/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
> index 9e08d69..e297d62 100644
> --- a/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
> +++ b/arch/arm/mach-omap2/omap_hwmod_54xx_data.c
> @@ -1544,7 +1544,8 @@ static struct omap_hwmod_class_sysconfig omap54xx_usb_host_hs_sysc = {
>  	.rev_offs	= 0x0000,
>  	.sysc_offs	= 0x0010,
>  	.sysc_flags	= (SYSC_HAS_MIDLEMODE | SYSC_HAS_RESET_STATUS |
> -			   SYSC_HAS_SIDLEMODE | SYSC_HAS_SOFTRESET),
> +			   SYSC_HAS_SIDLEMODE | SYSC_HAS_SOFTRESET |
> +			   SYSC_HAS_RESET_STATUS),
>  	.idlemodes	= (SIDLE_FORCE | SIDLE_NO | SIDLE_SMART |
>  			   SIDLE_SMART_WKUP | MSTANDBY_FORCE | MSTANDBY_NO |
>  			   MSTANDBY_SMART | MSTANDBY_SMART_WKUP),
> @@ -1598,15 +1599,7 @@ static struct omap_hwmod omap54xx_usb_host_hs_hwmod = {
>  	 * hence HWMOD_SWSUP_MSTANDBY
>  	 */
>  
> -	/*
> -	 * During system boot; If the hwmod framework resets the module
> -	 * the module will have smart idle settings; which can lead to deadlock
> -	 * (above Errata Id:i660); so, dont reset the module during boot;
> -	 * Use HWMOD_INIT_NO_RESET.
> -	 */
> -
> -	.flags		= HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY |
> -			  HWMOD_INIT_NO_RESET,
> +	.flags		= HWMOD_SWSUP_SIDLE | HWMOD_SWSUP_MSTANDBY,
>  	.main_clk	= "l3init_60m_fclk",
>  	.prcm = {
>  		.omap4 = {
> -- 
> 1.8.3.2
> 


- Paul


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