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

From: Anand Moon
Date: Fri May 08 2015 - 07:08:50 EST


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@xxxxxxxxxxx>
Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
---
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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