[PATCHv3] clk samsung exynos5420 add CLK_RECALC_NEW_RATES flag to mout_apll and mout_kpll clock.

Anand Moon linux.amoon at gmail.com
Fri May 8 04:07:27 PDT 2015


Addition of CLK_RECALC_NEW_RATES flag to support Exynos5420 cpu clk so that
correct divider values are re-calculated after both pre/post
clock notifiers had run for mout_apll clock and mout_kpll clock.

Observation their is considerable improvement in cpufreq stats
after applying this patch.

Governer : "performance"
$ cpupower -c 1 frequency-info

Below is table format of the output.
cpufreq stats:  Frequency| Before | After  |
CPU 1
		200 MHz  | 22.07% | 46.57% |
	       	300 MHz  | 1.08%  | 8.18%  |
	       	400 MHz  | 0.17%  | 1.93%  |
	       	500 MHz  | 0.24%  | 3.51%  |
	       	600 MHz  | 0.37%  | 2.13%  |
	       	700 MHz  | 0.20%  | 0.88%  |
	       	800 MHz  | 0.09%  | 1.69%  |
		900 MHz  | 0.05%  | 1.02%  |
		1000 MHz | 0.02%  | 2.55%  |
		1.10 GHz | 0.12%  | 1.17%  |
		1.20 GHz | 0.05%  | 0.88%  |
		1.30 GHz | 0.07%  | 0.38%  |
		1.40 GHz | 0.04%  | 0.38%  |
		1.50 GHz | 0.02%  | 0.00%  |
		1.60 GHz | 0.00%  | 0.15%  |
		1.70 GHz | 0.00%  | 0.44%  |
		1.80 GHz | 75.43% | 28.26% |

Governer : "performance"
$ cpupower -c 0 frequency-info

Below is table format of the output.
cpufreq stats:	Frequency| Before | After  |
CPU0 		200 MHz  | 33.95% | 60.31% |
		300 MHz  | 4.64%  | 2.13%  |
		400 MHz  | 1.50%  | 0.79%  |
		500 MHz  | 1.46%  | 0.49%  |
		600 MHz  | 0.05%  | 0.27%  |
		700 MHz  | 0.68%  | 0.21%  |
		800 MHz  | 0.08%  | 0.19%  |
		900 MHz  | 0.09%  | 0.12%  |
		1000 MHz | 0.20%  | 0.10%  |
		1.10 GHz | 0.21%  | 0.11%, |
		1.20 GHz | 0.51%  | 0.28%, |
		1.30 GHz | 56.64% | 35.01% |

Reviewed-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Signed-off-by: Anand Moon <linux.amoon at gmail.com>
---
 drivers/clk/samsung/clk-exynos5420.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
index 462aaee..6c7458c 100644
--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -618,10 +618,10 @@ static struct samsung_mux_clock exynos5x_mux_clks[] __initdata = {
 	MUX(0, "mout_mspll_cpu", mout_mspll_cpu_p, SRC_TOP7, 12, 2),
 
 	MUX_F(0, "mout_apll", mout_apll_p, SRC_CPU, 0, 1,
-	      CLK_SET_RATE_PARENT, 0),
+	      CLK_SET_RATE_PARENT | CLK_RECALC_NEW_RATES, 0),
 	MUX(0, "mout_cpu", mout_cpu_p, SRC_CPU, 16, 1),
 	MUX_F(0, "mout_kpll", mout_kpll_p, SRC_KFC, 0, 1,
-	      CLK_SET_RATE_PARENT, 0),
+	      CLK_SET_RATE_PARENT | CLK_RECALC_NEW_RATES, 0),
 	MUX(0, "mout_kfc", mout_kfc_p, SRC_KFC, 16, 1),
 
 	MUX(0, "mout_aclk200", mout_group1_p, SRC_TOP0, 8, 2),
-- 
1.9.1




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