On 2016/1/14 21:16, xuejiancheng wrote: > Hi Mike, > > On 2016/1/14 2:57, Michael Turquette wrote: >> Quoting xuejiancheng (2016-01-12 19:03:01) >>> Hi Stephen, >>> Thank you very much for your reply. >>> >>> On 2016/1/13 6:12, Stephen Boyd wrote: >>>> On 01/08, Jiancheng Xue wrote: >>>>> diff --git a/drivers/clk/hisilicon/Kconfig b/drivers/clk/hisilicon/Kconfig >>>>> index e434854..b6baebf 100644 >>>>> --- a/drivers/clk/hisilicon/Kconfig >>>>> +++ b/drivers/clk/hisilicon/Kconfig >>>>> @@ -1,3 +1,10 @@ >>>>> +config COMMON_CLK_HI3519 >>>>> + tristate "Clock Driver for Hi3519" >>>> >>>> It looks like this has to be bool. Otherwise it needs to be a >>>> platform driver and the hisilicon APIs need to be exported and >>>> lose their __init markings. >>>> >>> Yes,it's a problem. I will fix it in next version. Thank you. >> >> The best solution would be to make this clock driver a real platform >> driver. >> > Now the work clock of the clocksource timer-sp804 is provided by this driver. So > it need to be registered early by CLK_OF_DECLARE. If the timer clock is treated > as a fixed-clock provider, this driver can be implemented as a platform driver. > Then the crg device must be registered before other clock consumer devices.Accordingly > the crg device node must be written above all other clock consumer devices node in dts files. > I think it is also a dependence. > > Can you help me understand why it is better to make this driver a platform driver? > Thank you very much! > arch_initcall(customize_machine) -->of_platform_populate -->of_platform_bus_create -->of_amba_device_create -->amba_device_add -->amba_get_enable_pclk The call sequence above shows that the clock of the amba device must be registered before amba_device_add. The clock of "arm,pl011" uart is registered in the probe function of the platform driver "hi3519-crg". So the platform device "hi3519-crg" must be created before the amba device "arm,pl011" uart. If this is not a problem, I'll change this to a platform driver in next version. Thank you. Regards, Jiancheng >> Regards, >> Mike >> >>> >>>>> + depends on ARCH_HISI >>>>> + default y >>>>> + help >>>>> + Build the clock driver for hi3519. >>>>> + >>>>> config COMMON_CLK_HI6220 >>>>> bool "Hi6220 Clock Driver" >>>>> depends on ARCH_HISI || COMPILE_TEST >>>>> diff --git a/drivers/clk/hisilicon/clk-hi3519.c b/drivers/clk/hisilicon/clk-hi3519.c >>>>> new file mode 100644 >>>>> index 0000000..72d3a7b0 >>>>> --- /dev/null >>>>> +++ b/drivers/clk/hisilicon/clk-hi3519.c >>>>> @@ -0,0 +1,105 @@ >>>>> + >>>>> +#define HI3519_FIXED_24M (HI3519_EXT_CLKS + 1) >>>>> +#define HI3519_FIXED_50M (HI3519_EXT_CLKS + 2) >>>>> +#define HI3519_FIXED_75M (HI3519_EXT_CLKS + 3) >>>>> +#define HI3519_FIXED_125M (HI3519_EXT_CLKS + 4) >>>>> +#define HI3519_FIXED_150M (HI3519_EXT_CLKS + 5) >>>>> +#define HI3519_FIXED_200M (HI3519_EXT_CLKS + 6) >>>>> +#define HI3519_FIXED_250M (HI3519_EXT_CLKS + 7) >>>>> +#define HI3519_FIXED_300M (HI3519_EXT_CLKS + 8) >>>>> +#define HI3519_FIXED_400M (HI3519_EXT_CLKS + 9) >>>>> +#define HI3519_FMC_MUX (HI3519_EXT_CLKS + 10) >>>>> + >>>>> +#define HI3519_NR_CLKS 128 >>>> >>>> Is this the same clock provider as the external clocks? I don't >>>> understand why we're offsetting the clock numbering if we have >>>> different providers. And if these are truly fixed clocks (except >>>> for the mux) perhaps they're not even provided by this hardware >>>> block, and are clocks that come from the board? If that's true >>>> then I would expect them to be described in DT as fixed rate >>>> clocks. >>>> >>> External clocks mentioned here are used directly as work clocks of other modules. >>> Clocks defined in this file (internal clocks) are used as parents of external >>> clocks. Internal clocks won't be referred by dts files and are just used in this driver. >>> So they are moved here from the header file. >>> >>> External clocks and internal clocks are all generated by this CRG block. The input clock >>> of the CRG block is always connected to a crystal oscillator on the board. So only one >>> clock provider is defined here. >>> >>> Some clocks generated by CRG won't change their rate during the system running. These clocks >>> are treated as fixed clocks here. >>> >>>>> + >>>>> +static struct hisi_fixed_rate_clock hi3519_fixed_rate_clks[] __initdata = { >>>>> + { HI3519_FIXED_3M, "3m", NULL, CLK_IS_ROOT, 3000000, }, >>>>> + { HI3519_FIXED_24M, "24m", NULL, CLK_IS_ROOT, 24000000, }, >>>>> + { HI3519_FIXED_50M, "50m", NULL, CLK_IS_ROOT, 50000000, }, >>>>> + { HI3519_FIXED_75M, "75m", NULL, CLK_IS_ROOT, 75000000, }, >>>>> + { HI3519_FIXED_125M, "125m", NULL, CLK_IS_ROOT, 125000000, }, >>>>> + { HI3519_FIXED_150M, "150m", NULL, CLK_IS_ROOT, 150000000, }, >>>>> + { HI3519_FIXED_200M, "200m", NULL, CLK_IS_ROOT, 200000000, }, >>>>> + { HI3519_FIXED_250M, "250m", NULL, CLK_IS_ROOT, 250000000, }, >>>>> + { HI3519_FIXED_300M, "300m", NULL, CLK_IS_ROOT, 300000000, }, >>>>> + { HI3519_FIXED_400M, "400m", NULL, CLK_IS_ROOT, 400000000, }, >>>>> +}; >>>>> + >>>>> +static const char *fmc_mux_p[] __initconst = { >>>> >>>> const char * const ? >>>> >>> >>> OK. >>> >>>>> + "24m", "75m", "125m", "150m", "200m", "250m", "300m", "400m", }; >>>>> +static u32 fmc_mux_table[] = {0, 1, 2, 3, 4, 5, 6, 7}; >>>>> + >>>>> +static struct hisi_mux_clock hi3519_mux_clks[] __initdata = { >>>>> + { HI3519_FMC_MUX, "fmc_mux", fmc_mux_p, ARRAY_SIZE(fmc_mux_p), >>>>> + CLK_SET_RATE_PARENT, 0xc0, 2, 3, 0, fmc_mux_table, }, >>>>> +}; >>>>> + >>>>> +static struct hisi_gate_clock hi3519_gate_clks[] __initdata = { >>>> >>>> We should look into making these things const. >>>> >>> OK. I'll add this in next version. >>> >>>>> + /* fmc */ >>>>> + { HI3519_FMC_CLK, "clk_fmc", "fmc_mux", >>>>> + CLK_SET_RATE_PARENT, 0xc0, 1, 0, }, >>>>> + /* uart */ >>>>> + { HI3519_UART0_CLK, "clk_uart0", "24m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 20, 0, }, >>>>> + { HI3519_UART1_CLK, "clk_uart1", "24m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 21, 0, }, >>>>> + { HI3519_UART2_CLK, "clk_uart2", "24m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 22, 0, }, >>>>> + { HI3519_UART3_CLK, "clk_uart3", "24m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 23, 0, }, >>>>> + { HI3519_UART4_CLK, "clk_uart4", "24m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 24, 0, }, >>>>> + { HI3519_SPI0_CLK, "clk_spi0", "50m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 16, 0, }, >>>>> + { HI3519_SPI1_CLK, "clk_spi1", "50m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 17, 0, }, >>>>> + { HI3519_SPI2_CLK, "clk_spi2", "50m", >>>>> + CLK_SET_RATE_PARENT, 0xe4, 18, 0, }, >>>>> +}; >>>>> + >>>>> +static void __init hi3519_clk_init(struct device_node *np) >>>>> +{ >>>>> + struct hisi_clock_data *clk_data; >>>>> + >>>>> + >>>>> + clk_data = hisi_clk_init(np, HI3519_NR_CLKS); >>>>> + if (!clk_data) >>>>> + return; >>>>> + >>>>> + hisi_clk_register_fixed_rate(hi3519_fixed_rate_clks, >>>>> + ARRAY_SIZE(hi3519_fixed_rate_clks), >>>>> + clk_data); >>>>> + hisi_clk_register_mux(hi3519_mux_clks, ARRAY_SIZE(hi3519_mux_clks), >>>>> + clk_data); >>>>> + hisi_clk_register_gate(hi3519_gate_clks, >>>>> + ARRAY_SIZE(hi3519_gate_clks), clk_data); >>>>> + >>>>> + hisi_reset_init(np); >>>>> +} >>>>> + >>>>> +CLK_OF_DECLARE(hi3519_clk, "hisilicon,hi3519-crg", hi3519_clk_init); >>>>> diff --git a/drivers/clk/hisilicon/reset.h b/drivers/clk/hisilicon/reset.h >>>>> new file mode 100644 >>>>> index 0000000..37856089 >>>>> --- /dev/null >>>>> +++ b/drivers/clk/hisilicon/reset.h >>>>> @@ -0,0 +1,32 @@ >>>>> +/* >>>>> + * Copyright (c) 2015 HiSilicon Technologies Co., Ltd. >>>>> + * >>>>> + * This program is free software; you can redistribute it and/or modify >>>>> + * it under the terms of the GNU General Public License as published by >>>>> + * the Free Software Foundation; either version 2 of the License, or >>>>> + * (at your option) any later version. >>>>> + * >>>>> + * This program is distributed in the hope that it will be useful, >>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>>>> + * GNU General Public License for more details. >>>>> + * >>>>> + * You should have received a copy of the GNU General Public License >>>>> + * along with this program. If not, see <http://www.gnu.org/licenses/>. >>>>> + */ >>>>> + >>>>> +#ifndef __HISI_RESET_H >>>>> +#define __HISI_RESET_H >>>>> + >>>>> +#include <linux/of.h> >>>> >>>> Drop this include and forward declare struct device_node instead. >>>> >>> >>> OK. >>> >>>>> + >>>>> +#ifdef CONFIG_RESET_CONTROLLER >>>>> +int __init hisi_reset_init(struct device_node *np); >>>> >>>> We don't need __init in header files. >>>> >>> OK. I'll remove it. Thank you. >>> >>> Jiancheng >>> . >>> >> >> . >> > > > . > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html