Commit 4b51ccbc authored by Joseph Lo's avatar Joseph Lo Committed by Stephen Warren
Browse files

ARM: dt: tegra: add bindings of power management configurations for PMC 



The PMC mostly controls the entry and exit of the system from different
sleep modes. Different platform or system may have different configurations.
The power management configurations of PMC is represented as some properties.
The system needs to define the properties when the system supports deep sleep
mode (i.e. suspend).

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: default avatarJoseph Lo <josephl@nvidia.com>
Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
parent e307cc89

Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt

+38 −0
Original line number Diff line number Diff line 
NVIDIA Tegra Power Management Controller (PMC)



The PMC block interacts with an external Power Management Unit. The PMC

mostly controls the entry and exit of the system from different sleep

modes. It provides power-gating controllers for SoC and CPU power-islands.



Required properties:

- name : Should be pmc

- compatible : Should contain "nvidia,tegra<chip>-pmc".
@@ -15,6 +19,32 @@ Optional properties: 
  signal is fed into the PMC. This signal is optionally inverted, and then

  fed into the ARM GIC. The PMC is not involved in the detection or

  handling of this interrupt signal, merely its inversion.

- nvidia,suspend-mode : The suspend mode that the platform should use.

  Valid values are 0, 1 and 2:

  0 (LP0): CPU + Core voltage off and DRAM in self-refresh

  1 (LP1): CPU voltage off and DRAM in self-refresh

  2 (LP2): CPU voltage off

- nvidia,core-power-req-active-high : Boolean, core power request active-high

- nvidia,sys-clock-req-active-high : Boolean, system clock request active-high

- nvidia,combined-power-req : Boolean, combined power request for CPU & Core

- nvidia,cpu-pwr-good-en : Boolean, CPU power good signal (from PMIC to PMC)

			   is enabled.



Required properties when nvidia,suspend-mode is specified:

- nvidia,cpu-pwr-good-time : CPU power good time in uS.

- nvidia,cpu-pwr-off-time : CPU power off time in uS.

- nvidia,core-pwr-good-time : <Oscillator-stable-time Power-stable-time>

			      Core power good time in uS.

- nvidia,core-pwr-off-time : Core power off time in uS.



Required properties when nvidia,suspend-mode=<0>:

- nvidia,lp0-vec : <start length> Starting address and length of LP0 vector

  The LP0 vector contains the warm boot code that is executed by AVP when

  resuming from the LP0 state. The AVP (Audio-Video Processor) is an ARM7

  processor and always being the first boot processor when chip is power on

  or resume from deep sleep mode. When the system is resumed from the deep

  sleep mode, the warm boot code will restore some PLLs, clocks and then

  bring up CPU0 for resuming the system.



Example:
@@ -25,6 +55,14 @@ pmc@7000f400 { 
	clocks = <&tegra_car 110>, <&clk32k_in>;

	clock-names = "pclk", "clk32k_in";

	nvidia,invert-interrupt;

	nvidia,suspend-mode = <1>;

	nvidia,cpu-pwr-good-time = <2000>;

	nvidia,cpu-pwr-off-time = <100>;

	nvidia,core-pwr-good-time = <3845 3845>;

	nvidia,core-pwr-off-time = <458>;

	nvidia,core-power-req-active-high;

	nvidia,sys-clock-req-active-high;

	nvidia,lp0-vec = <0xbdffd000 0x2000>;

};



/ Tegra board dts file

arch/arm/mach-tegra/pmc.c

+83 −0
Original line number Diff line number Diff line
@@ -21,6 +21,8 @@ 
#include <linux/of.h>

#include <linux/of_address.h>



#include "pmc.h"



#define PMC_CTRL			0x0

#define PMC_CTRL_INTR_LOW		(1 << 17)

#define PMC_PWRGATE_TOGGLE		0x30
@@ -49,6 +51,22 @@ static void __iomem *tegra_pmc_base; 
static bool tegra_pmc_invert_interrupt;

static struct clk *tegra_pclk;



struct pmc_pm_data {

	u32 cpu_good_time;	/* CPU power good time in uS */

	u32 cpu_off_time;	/* CPU power off time in uS */

	u32 core_osc_time;	/* Core power good osc time in uS */

	u32 core_pmu_time;	/* Core power good pmu time in uS */

	u32 core_off_time;	/* Core power off time in uS */

	bool corereq_high;	/* Core power request active-high */

	bool sysclkreq_high;	/* System clock request active-high */

	bool combined_req;	/* Combined pwr req for CPU & Core */

	bool cpu_pwr_good_en;	/* CPU power good signal is enabled */

	u32 lp0_vec_phy_addr;	/* The phy addr of LP0 warm boot code */

	u32 lp0_vec_size;	/* The size of LP0 warm boot code */

	enum tegra_suspend_mode suspend_mode;

};

static struct pmc_pm_data pmc_pm_data;



static inline u32 tegra_pmc_readl(u32 reg)

{

	return readl(tegra_pmc_base + reg);
@@ -176,6 +194,10 @@ static const struct of_device_id matches[] __initconst = { 
static void tegra_pmc_parse_dt(void)

{

	struct device_node *np;

	u32 prop;

	enum tegra_suspend_mode suspend_mode;

	u32 core_good_time[2] = {0, 0};

	u32 lp0_vec[2] = {0, 0};



	np = of_find_matching_node(NULL, matches);

	BUG_ON(!np);
@@ -186,6 +208,67 @@ static void tegra_pmc_parse_dt(void) 
				     "nvidia,invert-interrupt");

	tegra_pclk = of_clk_get_by_name(np, "pclk");

	WARN_ON(IS_ERR(tegra_pclk));



	/* Grabbing the power management configurations */

	if (of_property_read_u32(np, "nvidia,suspend-mode", &prop)) {

		suspend_mode = TEGRA_SUSPEND_NONE;

	} else {

		switch (prop) {

		case 0:

			suspend_mode = TEGRA_SUSPEND_LP0;

			break;

		case 1:

			suspend_mode = TEGRA_SUSPEND_LP1;

			break;

		case 2:

			suspend_mode = TEGRA_SUSPEND_LP2;

			break;

		default:

			suspend_mode = TEGRA_SUSPEND_NONE;

			break;

		}

	}



	if (of_property_read_u32(np, "nvidia,cpu-pwr-good-time", &prop))

		suspend_mode = TEGRA_SUSPEND_NONE;

	pmc_pm_data.cpu_good_time = prop;



	if (of_property_read_u32(np, "nvidia,cpu-pwr-off-time", &prop))

		suspend_mode = TEGRA_SUSPEND_NONE;

	pmc_pm_data.cpu_off_time = prop;



	if (of_property_read_u32_array(np, "nvidia,core-pwr-good-time",

			core_good_time, ARRAY_SIZE(core_good_time)))

		suspend_mode = TEGRA_SUSPEND_NONE;

	pmc_pm_data.core_osc_time = core_good_time[0];

	pmc_pm_data.core_pmu_time = core_good_time[1];



	if (of_property_read_u32(np, "nvidia,core-pwr-off-time",

				 &prop))

		suspend_mode = TEGRA_SUSPEND_NONE;

	pmc_pm_data.core_off_time = prop;



	pmc_pm_data.corereq_high = of_property_read_bool(np,

				"nvidia,core-power-req-active-high");



	pmc_pm_data.sysclkreq_high = of_property_read_bool(np,

				"nvidia,sys-clock-req-active-high");



	pmc_pm_data.combined_req = of_property_read_bool(np,

				"nvidia,combined-power-req");



	pmc_pm_data.cpu_pwr_good_en = of_property_read_bool(np,

				"nvidia,cpu-pwr-good-en");



	if (of_property_read_u32_array(np, "nvidia,lp0-vec", lp0_vec,

				       ARRAY_SIZE(lp0_vec)))

		if (suspend_mode == TEGRA_SUSPEND_LP0)

			suspend_mode = TEGRA_SUSPEND_LP1;



	pmc_pm_data.lp0_vec_phy_addr = lp0_vec[0];

	pmc_pm_data.lp0_vec_size = lp0_vec[1];



	pmc_pm_data.suspend_mode = suspend_mode;

}



void __init tegra_pmc_init(void)

arch/arm/mach-tegra/pmc.h

+8 −0
Original line number Diff line number Diff line
@@ -18,6 +18,14 @@ 
#ifndef __MACH_TEGRA_PMC_H

#define __MACH_TEGRA_PMC_H



enum tegra_suspend_mode {

	TEGRA_SUSPEND_NONE = 0,

	TEGRA_SUSPEND_LP2,	/* CPU voltage off */

	TEGRA_SUSPEND_LP1,	/* CPU voltage off, DRAM self-refresh */

	TEGRA_SUSPEND_LP0,      /* CPU + core voltage off, DRAM self-refresh */

	TEGRA_MAX_SUSPEND_MODE,

};



#ifdef CONFIG_PM_SLEEP

void set_power_timers(unsigned long us_on, unsigned long us_off);

#endif

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