linux-kernel - Re: [PATCH 3/3] clk: rockchip: do not gate the efuse256 clock

Open Source and information security mailing list archives

Date:	Mon, 10 Aug 2015 16:37:57 +0800
From:	Shunqian Zheng <zhengsq@...k-chips.com>
To:	Heiko Stübner <heiko@...ech.de>
CC:	linux-kernel@...r.kernel.org, dianders@...omium.org,
	linux-rockchip@...ts.infradead.org, xjq@...k-chips.com,
	srinivas.kandagatla@...aro.org, caesar.wang@...k-chips.com,
	maxime.ripard@...e-electrons.com
Subject: Re: [PATCH 3/3] clk: rockchip: do not gate the efuse256 clock

Hi Heiko,

On 2015年08月10日 16:08, Heiko Stübner wrote:
> Hi,
>
> Am Montag, 10. August 2015, 11:22:43 schrieb Shunqian Zheng:
>> From: ZhengShunQian <zhengsq@...k-chips.com>
>>
>> Always enable the clock of efuse256. Base on the nvmem framework,
>> it seems like there is not a good way to enable the clock
>> when actual needed.
>>
>> Signed-off-by: ZhengShunQian <zhengsq@...k-chips.com>
> actually regmap already provides a handle to have a clock for mmio-based
> regmaps ... take a look at devm_regmap_init_mmio_clk() [0]
Srinivas also suggested devm_regmap_init_mmio_clk() too, but unfortunately
mmio uses its own .read/.write callback that not suitable for eFuse.
>
> If this doesn't help, you can also simply clk_get and clk_prepare_enable the
> clock in your rockchip_efuse_probe() and disable in rockchip_efuse_remove().
Sure, I will use this way.
Thank you!!
>
>
> But I certainly don't want to extend the range of clocks magically staying
> enabled through the ccf.
>
>
> Heiko
>
>
> [0] http://lxr.free-electrons.com/source/drivers/base/regmap/regmap-mmio.c#L336
>
>
>> ---
>>   drivers/clk/rockchip/clk-rk3288.c      | 2 +-
>>   include/dt-bindings/clock/rk3288-cru.h | 1 +
>>   2 files changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/clk/rockchip/clk-rk3288.c
>> b/drivers/clk/rockchip/clk-rk3288.c index 0df5bae..84d9218 100644
>> --- a/drivers/clk/rockchip/clk-rk3288.c
>> +++ b/drivers/clk/rockchip/clk-rk3288.c
>> @@ -647,7 +647,7 @@ static struct rockchip_clk_branch rk3288_clk_branches[]
>> __initdata = { GATE(0, "pclk_efuse_1024", "pclk_cpu", 0,
>> RK3288_CLKGATE_CON(11), 2, GFLAGS), GATE(PCLK_TZPC, "pclk_tzpc",
>> "pclk_cpu", 0, RK3288_CLKGATE_CON(11), 3, GFLAGS), GATE(PCLK_UART2,
>> "pclk_uart2", "pclk_cpu", 0, RK3288_CLKGATE_CON(11), 9, GFLAGS), -	GATE(0,
>> "pclk_efuse_256", "pclk_cpu", 0, RK3288_CLKGATE_CON(11), 10, GFLAGS),
>> +	GATE(PCLK_EFUSE256, "pclk_efuse_256", "pclk_cpu", CLK_IGNORE_UNUSED,
>> RK3288_CLKGATE_CON(11), 10, GFLAGS), GATE(PCLK_RKPWM, "pclk_rkpwm",
>> "pclk_cpu", CLK_IGNORE_UNUSED, RK3288_CLKGATE_CON(11), 11, GFLAGS),
>>
>>   	/* ddrctrl [DDR Controller PHY clock] gates */
>> diff --git a/include/dt-bindings/clock/rk3288-cru.h
>> b/include/dt-bindings/clock/rk3288-cru.h index c719aac..ab74d5e 100644
>> --- a/include/dt-bindings/clock/rk3288-cru.h
>> +++ b/include/dt-bindings/clock/rk3288-cru.h
>> @@ -164,6 +164,7 @@
>>   #define PCLK_DDRUPCTL1		366
>>   #define PCLK_PUBL1		367
>>   #define PCLK_WDT		368
>> +#define PCLK_EFUSE256		369
>>
>>   /* hclk gates */
>>   #define HCLK_GPS		448
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@...ts.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip
>
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives