[PATCH v4 3/5] soc: bcm: bcm2835-pm: Add support for power domains under a new binding.
From: Eric Anholt
Date: Wed Dec 12 2018 - 18:52:17 EST
This provides a free software alternative to raspberrypi-power.c's
firmware calls to manage power domains. It also exposes a reset line,
where previously the vc4 driver had to try to force power off the
domain in order to trigger a reset.
Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
---
v4: no change
drivers/mfd/bcm2835-pm.c | 36 +-
drivers/soc/bcm/Kconfig | 11 +
drivers/soc/bcm/Makefile | 1 +
drivers/soc/bcm/bcm2835-power.c | 661 +++++++++++++++++++++++++++
include/dt-bindings/soc/bcm2835-pm.h | 28 ++
include/linux/mfd/bcm2835-pm.h | 1 +
6 files changed, 734 insertions(+), 4 deletions(-)
create mode 100644 drivers/soc/bcm/bcm2835-power.c
create mode 100644 include/dt-bindings/soc/bcm2835-pm.h
diff --git a/drivers/mfd/bcm2835-pm.c b/drivers/mfd/bcm2835-pm.c
index 53839e6a81e7..42fe67f1538e 100644
--- a/drivers/mfd/bcm2835-pm.c
+++ b/drivers/mfd/bcm2835-pm.c
@@ -3,7 +3,7 @@
* PM MFD driver for Broadcom BCM2835
*
* This driver binds to the PM block and creates the MFD device for
- * the WDT driver.
+ * the WDT and power drivers.
*/
#include <linux/delay.h>
@@ -21,11 +21,16 @@ static const struct mfd_cell bcm2835_pm_devs[] = {
{ .name = "bcm2835-wdt" },
};
+static const struct mfd_cell bcm2835_power_devs[] = {
+ { .name = "bcm2835-power" },
+};
+
static int bcm2835_pm_probe(struct platform_device *pdev)
{
struct resource *res;
struct device *dev = &pdev->dev;
struct bcm2835_pm *pm;
+ int ret;
pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
if (!pm)
@@ -39,13 +44,36 @@ static int bcm2835_pm_probe(struct platform_device *pdev)
if (IS_ERR(pm->base))
return PTR_ERR(pm->base);
- return devm_mfd_add_devices(dev, -1,
- bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
- NULL, 0, NULL);
+ ret = devm_mfd_add_devices(dev, -1,
+ bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
+ NULL, 0, NULL);
+ if (ret)
+ return ret;
+
+ /* We'll use the presence of the AXI ASB regs in the
+ * bcm2835-pm binding as the key for whether we can reference
+ * the full PM register range and support power domains.
+ */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (res) {
+ pm->asb = devm_ioremap_resource(dev, res);
+ if (IS_ERR(pm->asb))
+ return PTR_ERR(pm->asb);
+
+ ret = devm_mfd_add_devices(dev, -1,
+ bcm2835_power_devs,
+ ARRAY_SIZE(bcm2835_power_devs),
+ NULL, 0, NULL);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
}
static const struct of_device_id bcm2835_pm_of_match[] = {
{ .compatible = "brcm,bcm2835-pm-wdt", },
+ { .compatible = "brcm,bcm2835-pm", },
{},
};
MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
diff --git a/drivers/soc/bcm/Kconfig b/drivers/soc/bcm/Kconfig
index 055a845ed979..fe1af29560e9 100644
--- a/drivers/soc/bcm/Kconfig
+++ b/drivers/soc/bcm/Kconfig
@@ -1,5 +1,16 @@
menu "Broadcom SoC drivers"
+config BCM2835_POWER
+ bool "BCM2835 power domain driver"
+ depends on ARCH_BCM2835 || (COMPILE_TEST && OF)
+ select PM_GENERIC_DOMAINS if PM
+ select RESET_CONTROLLER
+ help
+ This enables support for the BCM2835 power domains and reset
+ controller. Any usage of power domains by the Raspberry Pi
+ firmware means that Linux usage of the same power domain
+ must be accessed using the RASPBERRYPI_POWER driver
+
config RASPBERRYPI_POWER
bool "Raspberry Pi power domain driver"
depends on ARCH_BCM2835 || (COMPILE_TEST && OF)
diff --git a/drivers/soc/bcm/Makefile b/drivers/soc/bcm/Makefile
index dc4fced72d21..c81df4b2403c 100644
--- a/drivers/soc/bcm/Makefile
+++ b/drivers/soc/bcm/Makefile
@@ -1,2 +1,3 @@
+obj-$(CONFIG_BCM2835_POWER) += bcm2835-power.o
obj-$(CONFIG_RASPBERRYPI_POWER) += raspberrypi-power.o
obj-$(CONFIG_SOC_BRCMSTB) += brcmstb/
diff --git a/drivers/soc/bcm/bcm2835-power.c b/drivers/soc/bcm/bcm2835-power.c
new file mode 100644
index 000000000000..48412957ec7a
--- /dev/null
+++ b/drivers/soc/bcm/bcm2835-power.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Power domain driver for Broadcom BCM2835
+ *
+ * Copyright (C) 2018 Broadcom
+ */
+
+#include <dt-bindings/soc/bcm2835-pm.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/bcm2835-pm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/reset-controller.h>
+#include <linux/types.h>
+
+#define PM_GNRIC 0x00
+#define PM_AUDIO 0x04
+#define PM_STATUS 0x18
+#define PM_RSTC 0x1c
+#define PM_RSTS 0x20
+#define PM_WDOG 0x24
+#define PM_PADS0 0x28
+#define PM_PADS2 0x2c
+#define PM_PADS3 0x30
+#define PM_PADS4 0x34
+#define PM_PADS5 0x38
+#define PM_PADS6 0x3c
+#define PM_CAM0 0x44
+#define PM_CAM0_LDOHPEN BIT(2)
+#define PM_CAM0_LDOLPEN BIT(1)
+#define PM_CAM0_CTRLEN BIT(0)
+
+#define PM_CAM1 0x48
+#define PM_CAM1_LDOHPEN BIT(2)
+#define PM_CAM1_LDOLPEN BIT(1)
+#define PM_CAM1_CTRLEN BIT(0)
+
+#define PM_CCP2TX 0x4c
+#define PM_CCP2TX_LDOEN BIT(1)
+#define PM_CCP2TX_CTRLEN BIT(0)
+
+#define PM_DSI0 0x50
+#define PM_DSI0_LDOHPEN BIT(2)
+#define PM_DSI0_LDOLPEN BIT(1)
+#define PM_DSI0_CTRLEN BIT(0)
+
+#define PM_DSI1 0x54
+#define PM_DSI1_LDOHPEN BIT(2)
+#define PM_DSI1_LDOLPEN BIT(1)
+#define PM_DSI1_CTRLEN BIT(0)
+
+#define PM_HDMI 0x58
+#define PM_HDMI_RSTDR BIT(19)
+#define PM_HDMI_LDOPD BIT(1)
+#define PM_HDMI_CTRLEN BIT(0)
+
+#define PM_USB 0x5c
+/* The power gates must be enabled with this bit before enabling the LDO in the
+ * USB block.
+ */
+#define PM_USB_CTRLEN BIT(0)
+
+#define PM_PXLDO 0x60
+#define PM_PXBG 0x64
+#define PM_DFT 0x68
+#define PM_SMPS 0x6c
+#define PM_XOSC 0x70
+#define PM_SPAREW 0x74
+#define PM_SPARER 0x78
+#define PM_AVS_RSTDR 0x7c
+#define PM_AVS_STAT 0x80
+#define PM_AVS_EVENT 0x84
+#define PM_AVS_INTEN 0x88
+#define PM_DUMMY 0xfc
+
+#define PM_IMAGE 0x108
+#define PM_GRAFX 0x10c
+#define PM_PROC 0x110
+#define PM_ENAB BIT(12)
+#define PM_ISPRSTN BIT(8)
+#define PM_H264RSTN BIT(7)
+#define PM_PERIRSTN BIT(6)
+#define PM_V3DRSTN BIT(6)
+#define PM_ISFUNC BIT(5)
+#define PM_MRDONE BIT(4)
+#define PM_MEMREP BIT(3)
+#define PM_ISPOW BIT(2)
+#define PM_POWOK BIT(1)
+#define PM_POWUP BIT(0)
+#define PM_INRUSH_SHIFT 13
+#define PM_INRUSH_3_5_MA 0
+#define PM_INRUSH_5_MA 1
+#define PM_INRUSH_10_MA 2
+#define PM_INRUSH_20_MA 3
+#define PM_INRUSH_MASK (3 << PM_INRUSH_SHIFT)
+
+#define PM_PASSWORD 0x5a000000
+
+#define PM_WDOG_TIME_SET 0x000fffff
+#define PM_RSTC_WRCFG_CLR 0xffffffcf
+#define PM_RSTS_HADWRH_SET 0x00000040
+#define PM_RSTC_WRCFG_SET 0x00000030
+#define PM_RSTC_WRCFG_FULL_RESET 0x00000020
+#define PM_RSTC_RESET 0x00000102
+
+#define PM_READ(reg) readl(power->base + (reg))
+#define PM_WRITE(reg, val) writel(PM_PASSWORD | (val), power->base + (reg))
+
+#define ASB_BRDG_VERSION 0x00
+#define ASB_CPR_CTRL 0x04
+
+#define ASB_V3D_S_CTRL 0x08
+#define ASB_V3D_M_CTRL 0x0c
+#define ASB_ISP_S_CTRL 0x10
+#define ASB_ISP_M_CTRL 0x14
+#define ASB_H264_S_CTRL 0x18
+#define ASB_H264_M_CTRL 0x1c
+
+#define ASB_REQ_STOP BIT(0)
+#define ASB_ACK BIT(1)
+#define ASB_EMPTY BIT(2)
+#define ASB_FULL BIT(3)
+
+#define ASB_AXI_BRDG_ID 0x20
+
+#define ASB_READ(reg) readl(power->asb + (reg))
+#define ASB_WRITE(reg, val) writel(PM_PASSWORD | (val), power->asb + (reg))
+
+struct bcm2835_power_domain {
+ struct generic_pm_domain base;
+ struct bcm2835_power *power;
+ u32 domain;
+ struct clk *clk;
+};
+
+struct bcm2835_power {
+ struct device *dev;
+ /* PM registers. */
+ void __iomem *base;
+ /* AXI Async bridge registers. */
+ void __iomem *asb;
+
+ struct genpd_onecell_data pd_xlate;
+ struct bcm2835_power_domain domains[BCM2835_POWER_DOMAIN_COUNT];
+ struct reset_controller_dev reset;
+};
+
+static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg)
+{
+ u64 start = ktime_get_ns();
+
+ /* Enable the module's async AXI bridges. */
+ ASB_WRITE(reg, ASB_READ(reg) & ~ASB_REQ_STOP);
+ while (ASB_READ(reg) & ASB_ACK) {
+ cpu_relax();
+ if (ktime_get_ns() - start >= 1000)
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int bcm2835_asb_disable(struct bcm2835_power *power, u32 reg)
+{
+ u64 start = ktime_get_ns();
+
+ /* Enable the module's async AXI bridges. */
+ ASB_WRITE(reg, ASB_READ(reg) | ASB_REQ_STOP);
+ while (!(ASB_READ(reg) & ASB_ACK)) {
+ cpu_relax();
+ if (ktime_get_ns() - start >= 1000)
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int bcm2835_power_power_off(struct bcm2835_power_domain *pd, u32 pm_reg)
+{
+ struct bcm2835_power *power = pd->power;
+
+ /* Enable functional isolation */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISFUNC);
+
+ /* Enable electrical isolation */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISPOW);
+
+ /* Open the power switches. */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_POWUP);
+
+ return 0;
+}
+
+static int bcm2835_power_power_on(struct bcm2835_power_domain *pd, u32 pm_reg)
+{
+ struct bcm2835_power *power = pd->power;
+ struct device *dev = power->dev;
+ u64 start;
+ int ret;
+ int inrush;
+ bool powok;
+
+ /* If it was already powered on by the fw, leave it that way. */
+ if (PM_READ(pm_reg) & PM_POWUP)
+ return 0;
+
+ /* Enable power. Allowing too much current at once may result
+ * in POWOK never getting set, so start low and ramp it up as
+ * necessary to succeed.
+ */
+ powok = false;
+ for (inrush = PM_INRUSH_3_5_MA; inrush <= PM_INRUSH_20_MA; inrush++) {
+ PM_WRITE(pm_reg,
+ (PM_READ(pm_reg) & ~PM_INRUSH_MASK) |
+ (inrush << PM_INRUSH_SHIFT) |
+ PM_POWUP);
+
+ start = ktime_get_ns();
+ while (!(powok = !!(PM_READ(pm_reg) & PM_POWOK))) {
+ cpu_relax();
+ if (ktime_get_ns() - start >= 3000)
+ break;
+ }
+ }
+ if (!powok) {
+ dev_err(dev, "Timeout waiting for %s power OK\n",
+ pd->base.name);
+ ret = -ETIMEDOUT;
+ goto err_disable_powup;
+ }
+
+ /* Disable electrical isolation */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_ISPOW);
+
+ /* Repair memory */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_MEMREP);
+ start = ktime_get_ns();
+ while (!(PM_READ(pm_reg) & PM_MRDONE)) {
+ cpu_relax();
+ if (ktime_get_ns() - start >= 1000) {
+ dev_err(dev, "Timeout waiting for %s memory repair\n",
+ pd->base.name);
+ ret = -ETIMEDOUT;
+ goto err_disable_ispow;
+ }
+ }
+
+ /* Disable functional isolation */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_ISFUNC);
+
+ return 0;
+
+err_disable_ispow:
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISPOW);
+err_disable_powup:
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~(PM_POWUP | PM_INRUSH_MASK));
+ return ret;
+}
+
+static int bcm2835_asb_power_on(struct bcm2835_power_domain *pd,
+ u32 pm_reg,
+ u32 asb_m_reg,
+ u32 asb_s_reg,
+ u32 reset_flags)
+{
+ struct bcm2835_power *power = pd->power;
+ int ret;
+
+ ret = clk_prepare_enable(pd->clk);
+ if (ret) {
+ dev_err(power->dev, "Failed to enable clock for %s\n",
+ pd->base.name);
+ return ret;
+ }
+
+ /* Wait 32 clocks for reset to propagate, 1 us will be enough */
+ udelay(1);
+
+ clk_disable_unprepare(pd->clk);
+
+ /* Deassert the resets. */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) | reset_flags);
+
+ ret = clk_prepare_enable(pd->clk);
+ if (ret) {
+ dev_err(power->dev, "Failed to enable clock for %s\n",
+ pd->base.name);
+ goto err_enable_resets;
+ }
+
+ ret = bcm2835_asb_enable(power, asb_m_reg);
+ if (ret) {
+ dev_err(power->dev, "Failed to enable ASB master for %s\n",
+ pd->base.name);
+ goto err_disable_clk;
+ }
+ ret = bcm2835_asb_enable(power, asb_s_reg);
+ if (ret) {
+ dev_err(power->dev, "Failed to enable ASB slave for %s\n",
+ pd->base.name);
+ goto err_disable_asb_master;
+ }
+
+ return 0;
+
+err_disable_asb_master:
+ bcm2835_asb_disable(power, asb_m_reg);
+err_disable_clk:
+ clk_disable_unprepare(pd->clk);
+err_enable_resets:
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~reset_flags);
+ return ret;
+}
+
+static int bcm2835_asb_power_off(struct bcm2835_power_domain *pd,
+ u32 pm_reg,
+ u32 asb_m_reg,
+ u32 asb_s_reg,
+ u32 reset_flags)
+{
+ struct bcm2835_power *power = pd->power;
+ int ret;
+
+ ret = bcm2835_asb_disable(power, asb_s_reg);
+ if (ret) {
+ dev_warn(power->dev, "Failed to disable ASB slave for %s\n",
+ pd->base.name);
+ return ret;
+ }
+ ret = bcm2835_asb_disable(power, asb_m_reg);
+ if (ret) {
+ dev_warn(power->dev, "Failed to disable ASB master for %s\n",
+ pd->base.name);
+ bcm2835_asb_enable(power, asb_s_reg);
+ return ret;
+ }
+
+ clk_disable_unprepare(pd->clk);
+
+ /* Assert the resets. */
+ PM_WRITE(pm_reg, PM_READ(pm_reg) & ~reset_flags);
+
+ return 0;
+}
+
+static int bcm2835_power_pd_power_on(struct generic_pm_domain *domain)
+{
+ struct bcm2835_power_domain *pd =
+ container_of(domain, struct bcm2835_power_domain, base);
+ struct bcm2835_power *power = pd->power;
+
+ switch (pd->domain) {
+ case BCM2835_POWER_DOMAIN_GRAFX:
+ return bcm2835_power_power_on(pd, PM_GRAFX);
+
+ case BCM2835_POWER_DOMAIN_GRAFX_V3D:
+ return bcm2835_asb_power_on(pd, PM_GRAFX,
+ ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
+ PM_V3DRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE:
+ return bcm2835_power_power_on(pd, PM_IMAGE);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_PERI:
+ return bcm2835_asb_power_on(pd, PM_IMAGE,
+ 0, 0,
+ PM_PERIRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_ISP:
+ return bcm2835_asb_power_on(pd, PM_IMAGE,
+ ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
+ PM_ISPRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_H264:
+ return bcm2835_asb_power_on(pd, PM_IMAGE,
+ ASB_H264_M_CTRL, ASB_H264_S_CTRL,
+ PM_H264RSTN);
+
+ case BCM2835_POWER_DOMAIN_USB:
+ PM_WRITE(PM_USB, PM_USB_CTRLEN);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_DSI0:
+ PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN);
+ PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN | PM_DSI0_LDOHPEN);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_DSI1:
+ PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN);
+ PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN | PM_DSI1_LDOHPEN);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_CCP2TX:
+ PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN);
+ PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN | PM_CCP2TX_LDOEN);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_HDMI:
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_RSTDR);
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_CTRLEN);
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_LDOPD);
+ usleep_range(100, 200);
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_RSTDR);
+ return 0;
+
+ default:
+ dev_err(power->dev, "Invalid domain %d\n", pd->domain);
+ return -EINVAL;
+ }
+}
+
+static int bcm2835_power_pd_power_off(struct generic_pm_domain *domain)
+{
+ struct bcm2835_power_domain *pd =
+ container_of(domain, struct bcm2835_power_domain, base);
+ struct bcm2835_power *power = pd->power;
+
+ switch (pd->domain) {
+ case BCM2835_POWER_DOMAIN_GRAFX:
+ return bcm2835_power_power_off(pd, PM_GRAFX);
+
+ case BCM2835_POWER_DOMAIN_GRAFX_V3D:
+ return bcm2835_asb_power_off(pd, PM_GRAFX,
+ ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
+ PM_V3DRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE:
+ return bcm2835_power_power_off(pd, PM_IMAGE);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_PERI:
+ return bcm2835_asb_power_off(pd, PM_IMAGE,
+ 0, 0,
+ PM_PERIRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_ISP:
+ return bcm2835_asb_power_off(pd, PM_IMAGE,
+ ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
+ PM_ISPRSTN);
+
+ case BCM2835_POWER_DOMAIN_IMAGE_H264:
+ return bcm2835_asb_power_off(pd, PM_IMAGE,
+ ASB_H264_M_CTRL, ASB_H264_S_CTRL,
+ PM_H264RSTN);
+
+ case BCM2835_POWER_DOMAIN_USB:
+ PM_WRITE(PM_USB, 0);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_DSI0:
+ PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN);
+ PM_WRITE(PM_DSI0, 0);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_DSI1:
+ PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN);
+ PM_WRITE(PM_DSI1, 0);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_CCP2TX:
+ PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN);
+ PM_WRITE(PM_CCP2TX, 0);
+ return 0;
+
+ case BCM2835_POWER_DOMAIN_HDMI:
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_LDOPD);
+ PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_CTRLEN);
+ return 0;
+
+ default:
+ dev_err(power->dev, "Invalid domain %d\n", pd->domain);
+ return -EINVAL;
+ }
+}
+
+static void
+bcm2835_init_power_domain(struct bcm2835_power *power,
+ int pd_xlate_index, const char *name)
+{
+ struct device *dev = power->dev;
+ struct bcm2835_power_domain *dom = &power->domains[pd_xlate_index];
+
+ dom->clk = devm_clk_get(dev->parent, name);
+
+ dom->base.name = name;
+ dom->base.power_on = bcm2835_power_pd_power_on;
+ dom->base.power_off = bcm2835_power_pd_power_off;
+
+ dom->domain = pd_xlate_index;
+ dom->power = power;
+
+ /* XXX: on/off at boot? */
+ pm_genpd_init(&dom->base, NULL, true);
+
+ power->pd_xlate.domains[pd_xlate_index] = &dom->base;
+}
+
+/** bcm2835_reset_reset - Resets a block that has a reset line in the
+ * PM block.
+ *
+ * The consumer of the reset controller must have the power domain up
+ * -- there's no reset ability with the power domain down. To reset
+ * the sub-block, we just disable its access to memory through the
+ * ASB, reset, and re-enable.
+ */
+static int bcm2835_reset_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct bcm2835_power *power = container_of(rcdev, struct bcm2835_power,
+ reset);
+ struct bcm2835_power_domain *pd;
+ int ret;
+
+ switch (id) {
+ case BCM2835_RESET_V3D:
+ pd = &power->domains[BCM2835_POWER_DOMAIN_GRAFX_V3D];
+ break;
+ case BCM2835_RESET_H264:
+ pd = &power->domains[BCM2835_POWER_DOMAIN_IMAGE_H264];
+ break;
+ case BCM2835_RESET_ISP:
+ pd = &power->domains[BCM2835_POWER_DOMAIN_IMAGE_ISP];
+ break;
+ default:
+ dev_err(power->dev, "Bad reset id %ld\n", id);
+ return -EINVAL;
+ }
+
+ ret = bcm2835_power_pd_power_off(&pd->base);
+ if (ret)
+ return ret;
+
+ return bcm2835_power_pd_power_on(&pd->base);
+}
+
+static int bcm2835_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct bcm2835_power *power = container_of(rcdev, struct bcm2835_power,
+ reset);
+
+ switch (id) {
+ case BCM2835_RESET_V3D:
+ return !PM_READ(PM_GRAFX & PM_V3DRSTN);
+ case BCM2835_RESET_H264:
+ return !PM_READ(PM_IMAGE & PM_H264RSTN);
+ case BCM2835_RESET_ISP:
+ return !PM_READ(PM_IMAGE & PM_ISPRSTN);
+ default:
+ return -EINVAL;
+ }
+}
+
+const struct reset_control_ops bcm2835_reset_ops = {
+ .reset = bcm2835_reset_reset,
+ .status = bcm2835_reset_status,
+};
+
+static const char *const power_domain_names[] = {
+ [BCM2835_POWER_DOMAIN_GRAFX] = "grafx",
+ [BCM2835_POWER_DOMAIN_GRAFX_V3D] = "v3d",
+
+ [BCM2835_POWER_DOMAIN_IMAGE] = "image",
+ [BCM2835_POWER_DOMAIN_IMAGE_PERI] = "peri_image",
+ [BCM2835_POWER_DOMAIN_IMAGE_H264] = "h264",
+ [BCM2835_POWER_DOMAIN_IMAGE_ISP] = "isp",
+
+ [BCM2835_POWER_DOMAIN_USB] = "usb",
+ [BCM2835_POWER_DOMAIN_DSI0] = "dsi0",
+ [BCM2835_POWER_DOMAIN_DSI1] = "dsi1",
+ [BCM2835_POWER_DOMAIN_CAM0] = "cam0",
+ [BCM2835_POWER_DOMAIN_CAM1] = "cam1",
+ [BCM2835_POWER_DOMAIN_CCP2TX] = "ccp2tx",
+ [BCM2835_POWER_DOMAIN_HDMI] = "hdmi",
+};
+
+static int bcm2835_power_probe(struct platform_device *pdev)
+{
+ struct bcm2835_pm *pm = dev_get_drvdata(pdev->dev.parent);
+ struct device *dev = &pdev->dev;
+ struct bcm2835_power *power;
+ static const struct {
+ int parent, child;
+ } domain_deps[] = {
+ { BCM2835_POWER_DOMAIN_GRAFX, BCM2835_POWER_DOMAIN_GRAFX_V3D },
+ { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_PERI },
+ { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_H264 },
+ { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_ISP },
+ { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_USB },
+ { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_CAM0 },
+ { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_CAM1 },
+ };
+ int ret, i;
+ u32 id;
+
+ power = devm_kzalloc(dev, sizeof(*power), GFP_KERNEL);
+ if (!power)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, power);
+
+ power->dev = dev;
+ power->base = pm->base;
+ power->asb = pm->asb;
+
+ id = ASB_READ(ASB_AXI_BRDG_ID);
+ if (id != 0x62726467 /* "BRDG" */) {
+ dev_err(dev, "ASB register ID returned 0x%08x\n", id);
+ return -ENODEV;
+ }
+
+ power->pd_xlate.domains = devm_kcalloc(dev,
+ ARRAY_SIZE(power_domain_names),
+ sizeof(*power->pd_xlate.domains),
+ GFP_KERNEL);
+ if (!power->pd_xlate.domains)
+ return -ENOMEM;
+
+ power->pd_xlate.num_domains = ARRAY_SIZE(power_domain_names);
+
+ for (i = 0; i < ARRAY_SIZE(power_domain_names); i++)
+ bcm2835_init_power_domain(power, i, power_domain_names[i]);
+
+ for (i = 0; i < ARRAY_SIZE(domain_deps); i++) {
+ pm_genpd_add_subdomain(&power->domains[domain_deps[i].parent].base,
+ &power->domains[domain_deps[i].child].base);
+ }
+
+ power->reset.owner = THIS_MODULE;
+ power->reset.nr_resets = BCM2835_RESET_COUNT;
+ power->reset.ops = &bcm2835_reset_ops;
+ power->reset.of_node = dev->parent->of_node;
+
+ ret = devm_reset_controller_register(dev, &power->reset);
+ if (ret)
+ return ret;
+
+ of_genpd_add_provider_onecell(dev->parent->of_node, &power->pd_xlate);
+
+ dev_info(dev, "Broadcom BCM2835 power domains driver");
+ return 0;
+}
+
+static int bcm2835_power_remove(struct platform_device *pdev)
+{
+ return 0;
+}
+
+static struct platform_driver bcm2835_power_driver = {
+ .probe = bcm2835_power_probe,
+ .remove = bcm2835_power_remove,
+ .driver = {
+ .name = "bcm2835-power",
+ },
+};
+module_platform_driver(bcm2835_power_driver);
+
+MODULE_AUTHOR("Eric Anholt <eric@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM power domains and reset");
+MODULE_LICENSE("GPL");
diff --git a/include/dt-bindings/soc/bcm2835-pm.h b/include/dt-bindings/soc/bcm2835-pm.h
new file mode 100644
index 000000000000..153d75b8d99f
--- /dev/null
+++ b/include/dt-bindings/soc/bcm2835-pm.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+
+#ifndef _DT_BINDINGS_ARM_BCM2835_PM_H
+#define _DT_BINDINGS_ARM_BCM2835_PM_H
+
+#define BCM2835_POWER_DOMAIN_GRAFX 0
+#define BCM2835_POWER_DOMAIN_GRAFX_V3D 1
+#define BCM2835_POWER_DOMAIN_IMAGE 2
+#define BCM2835_POWER_DOMAIN_IMAGE_PERI 3
+#define BCM2835_POWER_DOMAIN_IMAGE_ISP 4
+#define BCM2835_POWER_DOMAIN_IMAGE_H264 5
+#define BCM2835_POWER_DOMAIN_USB 6
+#define BCM2835_POWER_DOMAIN_DSI0 7
+#define BCM2835_POWER_DOMAIN_DSI1 8
+#define BCM2835_POWER_DOMAIN_CAM0 9
+#define BCM2835_POWER_DOMAIN_CAM1 10
+#define BCM2835_POWER_DOMAIN_CCP2TX 11
+#define BCM2835_POWER_DOMAIN_HDMI 12
+
+#define BCM2835_POWER_DOMAIN_COUNT 13
+
+#define BCM2835_RESET_V3D 0
+#define BCM2835_RESET_ISP 1
+#define BCM2835_RESET_H264 2
+
+#define BCM2835_RESET_COUNT 3
+
+#endif /* _DT_BINDINGS_ARM_BCM2835_PM_H */
diff --git a/include/linux/mfd/bcm2835-pm.h b/include/linux/mfd/bcm2835-pm.h
index b7d0ee1feffa..ed37dc40e82a 100644
--- a/include/linux/mfd/bcm2835-pm.h
+++ b/include/linux/mfd/bcm2835-pm.h
@@ -8,6 +8,7 @@
struct bcm2835_pm {
struct device *dev;
void __iomem *base;
+ void __iomem *asb;
};
#endif /* BCM2835_MFD_PM_H */
--
2.20.0.rc1