2016-11-01 03:23:30

by Xing Zheng

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Subject: [PATCH] clk: rockchip: optimize the configuration for 800MHz and 1GHz on RK3399

Usually, the 800MHz and 1GHz are supplied for CPLL and NPLL in the RK3399.
But dues to the carelessly copying from RK3036 when the RK3399 bringing up,
the refdiv == 6, it will increase the lock time, and it is not an optimal
configuration.

Please let's fix them for the lock time and jitter are lower:
800 MHz:
- FVCO == 2.4 GHz, revdiv == 1.
1 GHz:
- FVCO == 3 GHz, revdiv == 1.

Signed-off-by: Xing Zheng <[email protected]>
---

drivers/clk/rockchip/clk-rk3399.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/rockchip/clk-rk3399.c b/drivers/clk/rockchip/clk-rk3399.c
index a5a3f41..28aff45 100644
--- a/drivers/clk/rockchip/clk-rk3399.c
+++ b/drivers/clk/rockchip/clk-rk3399.c
@@ -77,7 +77,7 @@ static struct rockchip_pll_rate_table rk3399_pll_rates[] = {
RK3036_PLL_RATE(1104000000, 1, 46, 1, 1, 1, 0),
RK3036_PLL_RATE(1100000000, 12, 550, 1, 1, 1, 0),
RK3036_PLL_RATE(1008000000, 1, 84, 2, 1, 1, 0),
- RK3036_PLL_RATE(1000000000, 6, 500, 2, 1, 1, 0),
+ RK3036_PLL_RATE(1000000000, 1, 125, 3, 1, 1, 0),
RK3036_PLL_RATE( 984000000, 1, 82, 2, 1, 1, 0),
RK3036_PLL_RATE( 960000000, 1, 80, 2, 1, 1, 0),
RK3036_PLL_RATE( 936000000, 1, 78, 2, 1, 1, 0),
@@ -87,7 +87,7 @@ static struct rockchip_pll_rate_table rk3399_pll_rates[] = {
RK3036_PLL_RATE( 864000000, 1, 72, 2, 1, 1, 0),
RK3036_PLL_RATE( 840000000, 1, 70, 2, 1, 1, 0),
RK3036_PLL_RATE( 816000000, 1, 68, 2, 1, 1, 0),
- RK3036_PLL_RATE( 800000000, 6, 400, 2, 1, 1, 0),
+ RK3036_PLL_RATE( 800000000, 1, 100, 3, 1, 1, 0),
RK3036_PLL_RATE( 700000000, 6, 350, 2, 1, 1, 0),
RK3036_PLL_RATE( 696000000, 1, 58, 2, 1, 1, 0),
RK3036_PLL_RATE( 676000000, 3, 169, 2, 1, 1, 0),
--
2.7.4



2016-11-01 23:25:49

by Heiko Stuebner

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Subject: Re: [PATCH] clk: rockchip: optimize the configuration for 800MHz and 1GHz on RK3399

Am Dienstag, 1. November 2016, 11:22:06 CET schrieb Xing Zheng:
> Usually, the 800MHz and 1GHz are supplied for CPLL and NPLL in the RK3399.
> But dues to the carelessly copying from RK3036 when the RK3399 bringing up,
> the refdiv == 6, it will increase the lock time, and it is not an optimal
> configuration.
>
> Please let's fix them for the lock time and jitter are lower:
> 800 MHz:
> - FVCO == 2.4 GHz, revdiv == 1.
> 1 GHz:
> - FVCO == 3 GHz, revdiv == 1.
>
> Signed-off-by: Xing Zheng <[email protected]>

applied to my clk-branch for 4.10


Thanks
Heiko