[U-Boot] [PATCH 3/6] ARM: AM43xx: Add support for disabling clocks in uboot
Lukasz Majewski
l.majewski at samsung.com
Tue Aug 11 09:01:03 CEST 2015
Hi Kishon,
> Add do_disable_clocks() to disable clock domains and module clocks.
> These clocks are enabled using do_enable_clocks().
Please correct the message subject. As fair as I can tell you are
changing clocks on am33xx SoC, not AM43xx.
>
> Cc: Roger Quadros <rogerq at ti.com>
> Cc: Tero Kristo <t-kristo at ti.com>
> Cc: Nishanth Menon <nm at ti.com>
> Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
> ---
> arch/arm/cpu/armv7/am33xx/clock.c | 53
> ++++++++++++++++++++++++++++++
> arch/arm/include/asm/arch-am33xx/clock.h | 1 + 2 files changed, 54
> insertions(+)
>
> diff --git a/arch/arm/cpu/armv7/am33xx/clock.c
> b/arch/arm/cpu/armv7/am33xx/clock.c index ec7d468..f6a4cee 100644
> --- a/arch/arm/cpu/armv7/am33xx/clock.c
> +++ b/arch/arm/cpu/armv7/am33xx/clock.c
> @@ -144,6 +144,34 @@ static inline void enable_clock_module(u32
> *const clkctrl_addr, u32 enable_mode,
> wait_for_clk_enable(clkctrl_addr); }
>
> +static inline void wait_for_clk_disable(u32 *clkctrl_addr)
> +{
> + u32 clkctrl, idlest = MODULE_CLKCTRL_IDLEST_FULLY_FUNCTIONAL;
> + u32 bound = LDELAY;
> +
> + while ((idlest != MODULE_CLKCTRL_IDLEST_DISABLED)) {
> + clkctrl = readl(clkctrl_addr);
> + idlest = (clkctrl & MODULE_CLKCTRL_IDLEST_MASK) >>
> + MODULE_CLKCTRL_IDLEST_SHIFT;
> + if (--bound == 0) {
> + printf("Clock disable failed for 0x%p idlest
> 0x%x\n",
> + clkctrl_addr, clkctrl);
> + return;
> + }
> + }
> +}
> +
> +static inline void disable_clock_module(u32 *const clkctrl_addr,
> + u32 wait_for_disable)
> +{
> + clrsetbits_le32(clkctrl_addr, MODULE_CLKCTRL_MODULEMODE_MASK,
> + MODULE_CLKCTRL_MODULEMODE_SW_DISABLE <<
> + MODULE_CLKCTRL_MODULEMODE_SHIFT);
> + debug("Disable clock module - %p\n", clkctrl_addr);
> + if (wait_for_disable)
> + wait_for_clk_disable(clkctrl_addr);
> +}
> +
> static inline void enable_clock_domain(u32 *const clkctrl_reg, u32
> enable_mode) {
> clrsetbits_le32(clkctrl_reg, CD_CLKCTRL_CLKTRCTRL_MASK,
> @@ -151,6 +179,14 @@ static inline void enable_clock_domain(u32
> *const clkctrl_reg, u32 enable_mode) debug("Enable clock domain -
> %p\n", clkctrl_reg); }
>
> +static inline void disable_clock_domain(u32 *const clkctrl_reg)
> +{
> + clrsetbits_le32(clkctrl_reg, CD_CLKCTRL_CLKTRCTRL_MASK,
> + CD_CLKCTRL_CLKTRCTRL_SW_SLEEP <<
> + CD_CLKCTRL_CLKTRCTRL_SHIFT);
> + debug("Disable clock domain - %p\n", clkctrl_reg);
> +}
> +
> void do_enable_clocks(u32 *const *clk_domains,
> u32 *const *clk_modules_explicit_en, u8
> wait_for_enable) {
> @@ -170,6 +206,23 @@ void do_enable_clocks(u32 *const *clk_domains,
> };
> }
>
> +void do_disable_clocks(u32 *const *clk_domains,
> + u32 *const *clk_modules_disable,
> + u8 wait_for_disable)
> +{
> + u32 i, max = 100;
> +
> +
Remove one blank line here.
> + /* Clock modules that need to be put in SW_DISABLE */
> + for (i = 0; (i < max) && clk_modules_disable[i]; i++)
> + disable_clock_module(clk_modules_disable[i],
> + wait_for_disable);
> +
> + /* Put the clock domains in SW_SLEEP mode */
> + for (i = 0; (i < max) && clk_domains[i]; i++)
> + disable_clock_domain(clk_domains[i]);
> +}
> +
> /*
> * Before scaling up the clocks we need to have the PMIC scale up the
> * voltages first. This will be dependent on which PMIC is in use
> diff --git a/arch/arm/include/asm/arch-am33xx/clock.h
> b/arch/arm/include/asm/arch-am33xx/clock.h index 4af6b57..a6d2419
> 100644 --- a/arch/arm/include/asm/arch-am33xx/clock.h
> +++ b/arch/arm/include/asm/arch-am33xx/clock.h
> @@ -112,5 +112,6 @@ void do_setup_dpll(const struct dpll_regs *,
> const struct dpll_params *); void prcm_init(void);
> void enable_basic_clocks(void);
> void do_enable_clocks(u32 *const *, u32 *const *, u8);
> +void do_disable_clocks(u32 *const *, u32 *const *, u8);
>
> #endif
--
Best regards,
Lukasz Majewski
Samsung R&D Institute Poland (SRPOL) | Linux Platform Group
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