Re: [PATCH 3/3] ARM: imx: enable RBC to support anatop LPM mode

From: Shawn Guo
Date: Wed Mar 20 2013 - 05:15:14 EST

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On Wed, Mar 20, 2013 at 01:39:40PM -0400, Anson Huang wrote:
> RBC is to control whether some ANATOP sub modules
> can enter lpm mode when SOC is into STOP mode, if
> RBC is enabled and PMIC_VSTBY_REQ is set, ANATOP
> will have below behaviors:
>
> 1. Digital LDOs(CORE, SOC and PU) are bypassed;
> 2. Analog LDOs(1P1, 2P5, 3P0) are disabled;
>
> As the 2P5 is necessary for DRAM IO pre-drive in
> STOP mode, so we need to enable weak 2P5 in STOP
> mode when 2P5 LDO is disabled.
>
> For RBC settings, there are some rules as below
> due to hardware designe:

s/designe/design

>
> 1. All interrupts must be masked during operating
> RBC registers;
> 2. At least 2 CKIL(32K) cycles is needed after the
> RBC setting is changed.
>
> Signed-off-by: Anson Huang <b20788@xxxxxxxxxxxxx>
> ---
> arch/arm/mach-imx/anatop.c | 19 +++++++++++++++++++
> arch/arm/mach-imx/clk-imx6q.c | 35 +++++++++++++++++++++++++++++++++++
> arch/arm/mach-imx/common.h | 3 +++
> arch/arm/mach-imx/gpc.c | 21 ++++++++++++++++++++-
> arch/arm/mach-imx/pm-imx6q.c | 2 ++
> 5 files changed, 79 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/mach-imx/anatop.c b/arch/arm/mach-imx/anatop.c
> index 8f6ab27..38b4f44 100644
> --- a/arch/arm/mach-imx/anatop.c
> +++ b/arch/arm/mach-imx/anatop.c
> @@ -18,12 +18,29 @@
>
> #define REG_SET 0x4
> #define REG_CLR 0x8
> +#define ANA_MISC0 0x150
> #define ANA_REG_CORE 0x140
> +#define ANA_REG_2P5 0x130

Please put these registers in acceding offset.

>
> +#define BM_ANADIG_REG_2P5_ENABLE_WEAK_LINREG 0x40000
> +#define BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG 0x1000
> #define BM_ANADIG_REG_CORE_FET_ODRIVE 0x20000000
>
> static struct regmap *anatop;
>
> +void imx_anatop_enable_weak2p5(bool enable)

static

> +{
> + u32 val;
> +
> + regmap_read(anatop, ANA_MISC0, &val);
> +
> + /* can only be enabled when stop_mode_config is clear. */
> + regmap_write(anatop, ANA_REG_2P5 + ((enable &&
> + ((val & BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG)
> + == 0)) ? REG_SET : REG_CLR),
> + BM_ANADIG_REG_2P5_ENABLE_WEAK_LINREG);

It's a little difficult to parse the expression even it's on the same
line, not mentioning with indentation. There are so many levels of
parentheses.

((enable && ((val & BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG) == 0)) ? REG_SET : REG_CLR)

What about rewriting it as below to make it easy for people to read?

reg = ANA_REG_2P5;
reg += (enable && (val & BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG) == 0) ?
REG_SET : REG_CLR;
regmap_write(anatop, reg, BM_ANADIG_REG_2P5_ENABLE_WEAK_LINREG);

> +}
> +
> void imx_anatop_enable_fet_odrive(bool enable)
> {
> regmap_write(anatop, ANA_REG_CORE + (enable ?
> @@ -32,12 +49,14 @@ void imx_anatop_enable_fet_odrive(bool enable)
>
> void imx_anatop_pre_suspend(void)
> {
> + imx_anatop_enable_weak2p5(true);
> imx_anatop_enable_fet_odrive(true);
> }
>
> void imx_anatop_post_resume(void)
> {
> imx_anatop_enable_fet_odrive(false);
> + imx_anatop_enable_weak2p5(false);
> }
>
> void __init imx_anatop_init(void)
> diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c
> index b365efc..646ce12 100644
> --- a/arch/arm/mach-imx/clk-imx6q.c
> +++ b/arch/arm/mach-imx/clk-imx6q.c
> @@ -14,6 +14,7 @@
> #include <linux/types.h>
> #include <linux/clk.h>
> #include <linux/clkdev.h>
> +#include <linux/delay.h>
> #include <linux/err.h>
> #include <linux/io.h>
> #include <linux/of.h>
> @@ -25,6 +26,8 @@
>
> #define CCR 0x0
> #define BM_CCR_WB_COUNT (0x7 << 16)
> +#define BM_CCR_RBC_BYPASS_COUNT (0x3f << 21)
> +#define BM_CCR_RBC_EN (0x1 << 27)
>
> #define CCGR0 0x68
> #define CCGR1 0x6c
> @@ -70,6 +73,38 @@ void imx6q_set_chicken_bit(void)
> writel_relaxed(val, ccm_base + CGPR);
> }
>
> +void imx6q_set_rbc(bool enable)

Same question as imx6q_set_wb, can we manage to call it in
imx6q_set_lpm()? The intension behind this is we should try to
a centralized place to configure CCM registers/bits for suspend
instead of exporting so many functions to suspend routine to call
individually.

> +{
> + u32 val;
> +
> + /*
> + * need to mask all interrupts in GPC before
> + * operating RBC configurations
> + */
> + imx_gpc_mask_all();
> +
> + /* configurate RBC enable bit */

s/configurate/configure

> + val = readl_relaxed(ccm_base + CCR);
> + val &= ~BM_CCR_RBC_EN;
> + val |= enable ? BM_CCR_RBC_EN : 0;
> + writel_relaxed(val, ccm_base + CCR);
> +
> + /* configurate RBC count */

Ditto

> + val = readl_relaxed(ccm_base + CCR);
> + val &= ~BM_CCR_RBC_BYPASS_COUNT;
> + val |= enable ? BM_CCR_RBC_BYPASS_COUNT : 0;
> + writel(val, ccm_base + CCR);
> +
> + /*
> + * need to delay at least 2 cycles of CKIL(32K)
> + * due to hardware design requirement, which is
> + * ~61us, here we use 65us for safe
> + */
> + udelay(65);

Nit, have a new line here.

> + /* restore GPC interrupt mask settings */
> + imx_gpc_restore_all();
> +}
> +
> void imx6q_set_wb(bool enable)
> {
> u32 val;
> diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
> index b9125cf..66fe41c 100644
> --- a/arch/arm/mach-imx/common.h
> +++ b/arch/arm/mach-imx/common.h
> @@ -129,11 +129,14 @@ extern void imx_src_prepare_restart(void);
> extern void imx_gpc_init(void);
> extern void imx_gpc_pre_suspend(void);
> extern void imx_gpc_post_resume(void);
> +extern void imx_gpc_mask_all(void);
> +extern void imx_gpc_restore_all(void);
> extern void imx_anatop_init(void);
> extern void imx_anatop_pre_suspend(void);
> extern void imx_anatop_post_resume(void);
> extern int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode);
> extern void imx6q_set_chicken_bit(void);
> +extern void imx6q_set_rbc(bool enable);
> extern void imx6q_set_wb(bool enable);

Since they are taking "enable" parameter, can we rename them as below?

void imx6q_enable_rbc(bool enable);
void imx6q_enable_wb(bool enable);

> extern void imx_cpu_die(unsigned int cpu);
> extern int imx_cpu_kill(unsigned int cpu);
> diff --git a/arch/arm/mach-imx/gpc.c b/arch/arm/mach-imx/gpc.c
> index a96ccc7..504049e 100644
> --- a/arch/arm/mach-imx/gpc.c
> +++ b/arch/arm/mach-imx/gpc.c
> @@ -1,5 +1,5 @@
> /*
> - * Copyright 2011 Freescale Semiconductor, Inc.
> + * Copyright 2011-2013 Freescale Semiconductor, Inc.
> * Copyright 2011 Linaro Ltd.
> *
> * The code contained herein is licensed under the GNU General Public
> @@ -68,6 +68,25 @@ static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
> return 0;
> }
>
> +void imx_gpc_mask_all(void)
> +{
> + void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
> + int i;
> +
> + for (i = 0; i < IMR_NUM; i++)
> + writel_relaxed(0xffffffff, reg_imr1 + i * 4);
> +
> +}
> +
> +void imx_gpc_restore_all(void)
> +{
> + void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
> + int i;
> +
> + for (i = 0; i < IMR_NUM; i++)
> + writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
> +}
> +
> static void imx_gpc_irq_unmask(struct irq_data *d)
> {
> void __iomem *reg;
> diff --git a/arch/arm/mach-imx/pm-imx6q.c b/arch/arm/mach-imx/pm-imx6q.c
> index 57ca274..24ac7bc 100644
> --- a/arch/arm/mach-imx/pm-imx6q.c
> +++ b/arch/arm/mach-imx/pm-imx6q.c
> @@ -36,10 +36,12 @@ static int imx6q_pm_enter(suspend_state_t state)
> imx_gpc_pre_suspend();

This call saves mask in gpc_saved_imrs and mask all interrupts except
those wakeup sources ...

> imx_anatop_pre_suspend();
> imx_set_cpu_jump(0, v7_cpu_resume);
> + imx6q_set_rbc(true);

At the end of imx6q_set_rbc(), imx_gpc_restore_all() will be called to
restore mask bits with gpc_saved_imrs, so wakeup source handling gets
lost, and any in-use interrupt will wake up system, which is
undesirable.

Shawn

> imx6q_set_wb(true);
> /* Zzz ... */
> cpu_suspend(0, imx6q_suspend_finish);
> imx6q_set_wb(false);
> + imx6q_set_rbc(false);
> imx_smp_prepare();
> imx_anatop_post_resume();
> imx_gpc_post_resume();
> --
> 1.7.9.5
>
>

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Next message: Miklos Szeredi: "Re: [PATCH 2/9] vfs: export do_splice_direct() to modules"
Previous message: Kishon Vijay Abraham I: "[PATCH v3 0/6] Generic PHY Framework"
In reply to: Anson Huang: "Re: [PATCH 3/3] ARM: imx: enable RBC to support anatop LPM mode"
Next in thread: Shawn Guo: "Re: [PATCH 1/3] ARM: imx: enable anatop suspend/resume"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]