[U-Boot] [PATCH v3 08/10] sun5/7i: add an implementation of the psci suspend function
Maxime Ripard
maxime.ripard at free-electrons.com
Wed Oct 26 14:38:10 CEST 2016
Hi,
On Wed, Oct 26, 2016 at 02:10:31PM +0200, Antoine Tenart wrote:
> Add the suspend psci function for sun5i and sun7i. Thus function
> switches the cpu clk source to osc24M or to losc depending on the
> SoC family.
>
> Signed-off-by: Antoine Tenart <antoine.tenart at free-electrons.com>
> ---
> arch/arm/cpu/armv7/sunxi/Makefile | 9 ++-
> arch/arm/cpu/armv7/sunxi/psci.c | 2 +-
> arch/arm/cpu/armv7/sunxi/psci_suspend.c | 108 ++++++++++++++++++++++++++
> arch/arm/include/asm/arch-sunxi/clock_sun4i.h | 6 ++
> 4 files changed, 123 insertions(+), 2 deletions(-)
> create mode 100644 arch/arm/cpu/armv7/sunxi/psci_suspend.c
>
> diff --git a/arch/arm/cpu/armv7/sunxi/Makefile b/arch/arm/cpu/armv7/sunxi/Makefile
> index b35b9df4a9d6..80667268a0fc 100644
> --- a/arch/arm/cpu/armv7/sunxi/Makefile
> +++ b/arch/arm/cpu/armv7/sunxi/Makefile
> @@ -13,7 +13,14 @@ obj-$(CONFIG_MACH_SUN6I) += tzpc.o
> obj-$(CONFIG_MACH_SUN8I_H3) += tzpc.o
>
> ifndef CONFIG_SPL_BUILD
> -obj-$(CONFIG_ARMV7_PSCI) += psci.o
> +ifdef CONFIG_ARMV7_PSCI
> +obj-$(CONFIG_MACH_SUN6I) += psci.o
> +obj-$(CONFIG_MACH_SUN7I) += psci.o
> +obj-$(CONFIG_MACH_SUN8I) += psci.o
> +
> +obj-$(CONFIG_MACH_SUN5I) += psci_suspend.o
> +obj-$(CONFIG_MACH_SUN7I) += psci_suspend.o
> +endif
> endif
>
> ifdef CONFIG_SPL_BUILD
> diff --git a/arch/arm/cpu/armv7/sunxi/psci.c b/arch/arm/cpu/armv7/sunxi/psci.c
> index 766b8c79d93d..4525bc7bf26b 100644
> --- a/arch/arm/cpu/armv7/sunxi/psci.c
> +++ b/arch/arm/cpu/armv7/sunxi/psci.c
> @@ -48,7 +48,7 @@ static u32 __secure cp15_read_cntp_ctl(void)
>
> #define ONE_MS (CONFIG_TIMER_CLK_FREQ / 1000)
>
> -static void __secure __mdelay(u32 ms)
> +void __secure __mdelay(u32 ms)
> {
> u32 reg = ONE_MS * ms;
>
> diff --git a/arch/arm/cpu/armv7/sunxi/psci_suspend.c b/arch/arm/cpu/armv7/sunxi/psci_suspend.c
> new file mode 100644
> index 000000000000..e5c000ff2d3d
> --- /dev/null
> +++ b/arch/arm/cpu/armv7/sunxi/psci_suspend.c
> @@ -0,0 +1,108 @@
> +/*
> + * Copyright (C) 2016 Antoine Tenart <antoine.tenart at free-electrons.com>
> + *
> + * Based on Allwinner code.
> + * Copyright 2007-2012 (C) Allwinner Technology Co., Ltd.
> + *
> + * SPDX-License-Identifier: GPL-2.0
> + */
> +#include <config.h>
> +#include <common.h>
> +
> +#include <asm/atomic.h>
> +#include <asm/arch/clock.h>
> +#include <asm/arch/dram.h>
> +#include <asm/armv7.h>
> +#include <asm/io.h>
> +#include <asm/psci.h>
> +#include <asm/secure.h>
> +#include <asm/system.h>
> +
> +#include <linux/bitops.h>
> +
> +void __mdelay(u32);
> +
> +#if defined(CONFIG_MACH_SUN5I)
> +#define NR_CPUS 1
> +#elif defined(CONFIG_MACH_SUN7I)
> +#define NR_CPUS 2
> +#endif
> +
> +/*
> + * The PSCI suspend function switch cpuclk to another source and disable
> + * pll1. As this function is called per-CPU, it should only do this when
> + * all the CPUs are in idle state.
> + *
> + * The 'cnt' variable keeps track of the number of CPU which are in the idle
> + * state. The last one setup cpuclk for idle.
> + *
> + * The 'clk_state' varibale holds the cpu clk state (idle or normal).
> + */
> +atomic_t __secure_data cnt, clk_state;
> +
> +#define CLK_NORMAL 0
> +#define CLK_IDLE 1
> +
> +static void __secure sunxi_clock_enter_idle(struct sunxi_ccm_reg *ccm)
> +{
> + /* switch cpuclk to osc24m */
> + clrsetbits_le32(&ccm->cpu_ahb_apb0_cfg, 0x3 << CPU_CLK_SRC_SHIFT,
> + CPU_CLK_SRC_OSC24M << CPU_CLK_SRC_SHIFT);
> +
> + /* disable pll1 */
> + clrbits_le32(&ccm->pll1_cfg, CCM_PLL1_CTRL_EN);
> +
> +#ifndef CONFIG_MACH_SUN7I
> + /* switch cpuclk to losc */
> + clrbits_le32(&ccm->cpu_ahb_apb0_cfg, 0x3 << CPU_CLK_SRC_SHIFT);
> +#endif
Some kind of comment here would be nice.
> +
> + /* disable ldo */
> + clrbits_le32(&ccm->osc24m_cfg, OSC24M_LDO_EN);
I realise I'm the one who suggested doing this, but that might turn
out to be wrong. Have you tested devices that use the oscillator
directly, like the PWM?
> +}
> +
> +static void __secure sunxi_clock_leave_idle(struct sunxi_ccm_reg *ccm)
> +{
> + /* enable ldo */
> + setbits_le32(&ccm->osc24m_cfg, OSC24M_LDO_EN);
> +
> +#ifndef CONFIG_MACH_SUN7I
> + /* switch cpuclk to osc24m */
> + clrsetbits_le32(&ccm->cpu_ahb_apb0_cfg, 0x3 << CPU_CLK_SRC_SHIFT,
> + CPU_CLK_SRC_OSC24M << CPU_CLK_SRC_SHIFT);
> +#endif
> +
> + /* enable pll1 */
> + setbits_le32(&ccm->pll1_cfg, CCM_PLL1_CTRL_EN);
It might be worth waiting for the PLL to lock by polling the bit 28
before switching the mux to it.
> +
> + /* switch cpuclk to pll1 */
> + clrsetbits_le32(&ccm->cpu_ahb_apb0_cfg, 0x3 << CPU_CLK_SRC_SHIFT,
> + CPU_CLK_SRC_PLL1 << CPU_CLK_SRC_SHIFT);
> +}
> +
> +void __secure psci_cpu_suspend(void)
> +{
> + struct sunxi_ccm_reg *ccm = (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
> +
> + if (atomic_inc_return(&cnt) == NR_CPUS) {
> + /* wait for any sunxi_clock_leave_idle() to finish */
> + while (atomic_read(&clk_state) != CLK_NORMAL)
> + __mdelay(1);
> +
> + sunxi_clock_enter_idle(ccm);
> + atomic_set(&clk_state, CLK_IDLE);
> + }
> +
> + /* idle */
> + DSB;
> + wfi();
> +
> + if (atomic_dec_return(&cnt) == NR_CPUS - 1) {
> + /* wait for any sunxi_clock_enter_idle() to finish */
> + while (atomic_read(&clk_state) != CLK_IDLE)
> + __mdelay(1);
> +
> + sunxi_clock_leave_idle(ccm);
> + atomic_set(&clk_state, CLK_NORMAL);
> + }
> +}
> diff --git a/arch/arm/include/asm/arch-sunxi/clock_sun4i.h b/arch/arm/include/asm/arch-sunxi/clock_sun4i.h
> index d1c5ad0a739b..0d7df5bba543 100644
> --- a/arch/arm/include/asm/arch-sunxi/clock_sun4i.h
> +++ b/arch/arm/include/asm/arch-sunxi/clock_sun4i.h
> @@ -90,6 +90,10 @@ struct sunxi_ccm_reg {
> u32 gmac_clk_cfg; /* 0x164 */
> };
>
> +/* osc24m_cfg bit field */
> +#define OSC24M_EN (0x1 << 0)
> +#define OSC24M_LDO_EN (0x1 << 16)
> +
> /* apb1 bit field */
> #define APB1_CLK_SRC_OSC24M (0x0 << 24)
> #define APB1_CLK_SRC_PLL6 (0x1 << 24)
> @@ -208,6 +212,8 @@ struct sunxi_ccm_reg {
> #define CCM_AHB_GATE_DLL (0x1 << 15)
> #define CCM_AHB_GATE_ACE (0x1 << 16)
>
> +#define CCM_PLL1_CTRL_EN (0x1 << 31)
> +
> #define CCM_PLL3_CTRL_M_SHIFT 0
> #define CCM_PLL3_CTRL_M_MASK (0x7f << CCM_PLL3_CTRL_M_SHIFT)
> #define CCM_PLL3_CTRL_M(n) (((n) & 0x7f) << 0)
> --
> 2.10.1
Looks good otherwise,
Thanks!
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: not available
URL: <http://lists.denx.de/pipermail/u-boot/attachments/20161026/6deb8447/attachment.sig>
More information about the U-Boot
mailing list