[PATCH 1/1] OMAP3: PM: SmartReflex: Fix scheduled while atomic problem

[PATCH 1/1] OMAP3: PM: SmartReflex: Fix scheduled while atomic problem

[Eduardo Valentin]

This patch moves clock lookup from get_vdd[1,2]_opp to
initialization procedure. Also adds a field in omap_sr
structure to store these clocks for later usage.

Calling clk_get inside get_vdd[1,2]_opp would cause
a scheduled while atomic problem while entering in idle
state (interrupts disabled).

Signed-off-by: Eduardo Valentin <eduardo.valentin@nokia.com>
---
 arch/arm/mach-omap2/smartreflex.c |   19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-omap2/smartreflex.c b/arch/arm/mach-omap2/smartreflex.c
index 8660863..8946e7c 100644
--- a/arch/arm/mach-omap2/smartreflex.c
+++ b/arch/arm/mach-omap2/smartreflex.c
@@ -43,6 +43,7 @@ struct omap_sr {
 	int		is_sr_reset;
 	int		is_autocomp_active;
 	struct clk	*clk;
+	struct clk	*vdd_opp_clk;
 	u32		clk_length;
 	u32		req_opp_no;
 	u32		opp1_nvalue, opp2_nvalue, opp3_nvalue, opp4_nvalue;
@@ -170,28 +171,24 @@ static u16 get_opp(struct omap_opp *opp_freq_table,
 static u16 get_vdd1_opp(void)
 {
 	u16 opp;
-	struct clk *clk;
 
-	clk = clk_get(NULL, "dpll1_ck");
-
-	if (clk == NULL || IS_ERR(clk) || mpu_opps == NULL)
+	if (sr1.vdd_opp_clk == NULL || IS_ERR(sr1.vdd_opp_clk) ||
+							mpu_opps == NULL)
 		return 0;
 
-	opp = get_opp(mpu_opps + MAX_VDD1_OPP, clk->rate);
+	opp = get_opp(mpu_opps + MAX_VDD1_OPP, sr1.vdd_opp_clk->rate);
 	return opp;
 }
 
 static u16 get_vdd2_opp(void)
 {
 	u16 opp;
-	struct clk *clk;
-
-	clk = clk_get(NULL, "l3_ick");
 
-	if (clk == NULL || IS_ERR(clk) || l3_opps == NULL)
+	if (sr2.vdd_opp_clk == NULL || IS_ERR(sr2.vdd_opp_clk) ||
+							l3_opps == NULL)
 		return 0;
 
-	opp = get_opp(l3_opps + MAX_VDD2_OPP, clk->rate);
+	opp = get_opp(l3_opps + MAX_VDD2_OPP, sr2.vdd_opp_clk->rate);
 	return opp;
 }
 
@@ -999,6 +996,8 @@ static int __init omap3_sr_init(void)
 		sr1.clk = clk_get(NULL, "sr1_fck");
 		sr2.clk = clk_get(NULL, "sr2_fck");
 	}
+	sr1.vdd_opp_clk = clk_get(NULL, "dpll1_ck");
+	sr2.vdd_opp_clk = clk_get(NULL, "l3_ick");
 	sr_set_clk_length(&sr1);
 	sr_set_clk_length(&sr2);
 
-- 
1.6.4.183.g04423

Re: [PATCH 1/1] OMAP3: PM: SmartReflex: Fix scheduled while atomic problem

[Kevin Hilman]

Eduardo Valentin <eduardo.valentin@nokia.com> writes:

> This patch moves clock lookup from get_vdd[1,2]_opp to
> initialization procedure. Also adds a field in omap_sr
> structure to store these clocks for later usage.
>
> Calling clk_get inside get_vdd[1,2]_opp would cause
> a scheduled while atomic problem while entering in idle
> state (interrupts disabled).
>
> Signed-off-by: Eduardo Valentin <eduardo.valentin@nokia.com>

Thanks, will pull into next PM branch.  Note that SR is in the middle
of a complete rewrite, so Nishanth, please ensure this fix is included
or verify that it is not needed in your rewrite.

Thanks,

Kevin

> ---
>  arch/arm/mach-omap2/smartreflex.c |   19 +++++++++----------
>  1 files changed, 9 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/smartreflex.c b/arch/arm/mach-omap2/smartreflex.c
> index 8660863..8946e7c 100644
> --- a/arch/arm/mach-omap2/smartreflex.c
> +++ b/arch/arm/mach-omap2/smartreflex.c
> @@ -43,6 +43,7 @@ struct omap_sr {
>  	int		is_sr_reset;
>  	int		is_autocomp_active;
>  	struct clk	*clk;
> +	struct clk	*vdd_opp_clk;
>  	u32		clk_length;
>  	u32		req_opp_no;
>  	u32		opp1_nvalue, opp2_nvalue, opp3_nvalue, opp4_nvalue;
> @@ -170,28 +171,24 @@ static u16 get_opp(struct omap_opp *opp_freq_table,
>  static u16 get_vdd1_opp(void)
>  {
>  	u16 opp;
> -	struct clk *clk;
>  
> -	clk = clk_get(NULL, "dpll1_ck");
> -
> -	if (clk == NULL || IS_ERR(clk) || mpu_opps == NULL)
> +	if (sr1.vdd_opp_clk == NULL || IS_ERR(sr1.vdd_opp_clk) ||
> +							mpu_opps == NULL)
>  		return 0;
>  
> -	opp = get_opp(mpu_opps + MAX_VDD1_OPP, clk->rate);
> +	opp = get_opp(mpu_opps + MAX_VDD1_OPP, sr1.vdd_opp_clk->rate);
>  	return opp;
>  }
>  
>  static u16 get_vdd2_opp(void)
>  {
>  	u16 opp;
> -	struct clk *clk;
> -
> -	clk = clk_get(NULL, "l3_ick");
>  
> -	if (clk == NULL || IS_ERR(clk) || l3_opps == NULL)
> +	if (sr2.vdd_opp_clk == NULL || IS_ERR(sr2.vdd_opp_clk) ||
> +							l3_opps == NULL)
>  		return 0;
>  
> -	opp = get_opp(l3_opps + MAX_VDD2_OPP, clk->rate);
> +	opp = get_opp(l3_opps + MAX_VDD2_OPP, sr2.vdd_opp_clk->rate);
>  	return opp;
>  }
>  
> @@ -999,6 +996,8 @@ static int __init omap3_sr_init(void)
>  		sr1.clk = clk_get(NULL, "sr1_fck");
>  		sr2.clk = clk_get(NULL, "sr2_fck");
>  	}
> +	sr1.vdd_opp_clk = clk_get(NULL, "dpll1_ck");
> +	sr2.vdd_opp_clk = clk_get(NULL, "l3_ick");
>  	sr_set_clk_length(&sr1);
>  	sr_set_clk_length(&sr2);
>  
> -- 
> 1.6.4.183.g04423