Re: [PATCH v2 2/2] mfd: rk808: Add restart functionality

From: Daniel Schultz
Date: Tue Mar 13 2018 - 05:46:36 EST

Hi,

I can add a DTS property to enable the PMIC restart functions? So this feature can be used if its desired.

My problem with the CRU reset is a strange behaviour in the ROM code. During a reset from MMC1 (eMMC), the ROM tries to load the SPL from MMC0 (SD).

Daniel


On 03/13/2018 04:32 AM, Joseph Chen wrote:
Hi, Danielï

ÂÂÂ ÂÂÂ On Rockchip platforms, we always use CRU to restart system. From your patch, I think you would like to support restart by CRU or PMIC, right ?

ÂÂÂ ÂÂÂ I think restart by PMIC is not accepted, because PMIC restart means all regualtors are reset (voltage drops to 0mv and then power on again), including vdd_arm, vdd_logic, vcc_ddr, etc. This is like a cold boot for machine.

ÂÂÂ ÂÂ We use CRU reset, because we want to keep status of last log, GRF, CRU or other registers, but PMIC restart can make them lost.


å 2018/3/12 22:10, Lee Jones åé:
Rockchip guys,

I'd really appreciate your input on these two patches please.

Please provide Reviewed-by/Tested-by tags.

On Wed, 07 Mar 2018, Daniel Schultz wrote:
When using Rockchip SoCs with rk805/808/818 PMICs, restarts are realized by
setting the reset registers in the "Clock and Reset Unit".

Since all three shutdown functions have almost the same code, all logic
from the shutdown functions can be refactored to a new function
"rk808_update_bits", which can update a register by a given address and
bitmask.

After that, notifier blocks and the restart functions were added to the
driver. Like the shutdown function, the restart is bound to the
"rockchip,system-power-controller" device tree property and can easily
revoked to the software restart by removing the property.

Signed-off-by: Daniel Schultz <d.schultz@xxxxxxxxx>
---
Changes:
ÂÂÂÂv2: Re-submit with recipients from Rockchip.

 drivers/mfd/rk808.c | 97 ++++++++++++++++++++++++++++++-----------------
 include/linux/mfd/rk808.h | 1 +
 2 files changed, 63 insertions(+), 35 deletions(-)

diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
index d138721..2c68f8c 100644
--- a/drivers/mfd/rk808.c
+++ b/drivers/mfd/rk808.c
@@ -27,6 +27,7 @@
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/regmap.h>
+#include <linux/reboot.h>
  struct rk808_reg_data {
ÂÂÂÂÂ int addr;
@@ -369,59 +370,73 @@ static const struct regmap_irq_chip rk818_irq_chip = {
  static struct i2c_client *rk808_i2c_client;
 -static void rk805_device_shutdown(void)
+static void rk808_update_bits(unsigned int reg, unsigned int bit_mask)
 {
ÂÂÂÂÂ int ret;
ÂÂÂÂÂ struct rk808 *rk808 = i2c_get_clientdata(rk808_i2c_client);
 Â if (!rk808) {
ÂÂÂÂÂÂÂÂÂ dev_warn(&rk808_i2c_client->dev,
-ÂÂÂÂÂÂÂÂÂÂÂÂ "have no rk805, so do nothing here\n");
+ÂÂÂÂÂÂÂÂÂÂÂÂ "have no %s, so do nothing here\n",
+ÂÂÂÂÂÂÂÂÂÂÂÂ rk808->regmap_irq_chip->name);
ÂÂÂÂÂÂÂÂÂ return;
ÂÂÂÂÂ }
 Â ret = regmap_update_bits(rk808->regmap,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ RK805_DEV_CTRL_REG,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ DEV_OFF, DEV_OFF);
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ reg,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ bit_mask, bit_mask);
ÂÂÂÂÂ if (ret)
-ÂÂÂÂÂÂÂ dev_err(&rk808_i2c_client->dev, "power off error!\n");
+ÂÂÂÂÂÂÂ dev_err(&rk808_i2c_client->dev, "can't write to DEVCTRL: %x!\n",
+ÂÂÂÂÂÂÂÂÂÂÂ ret);
 }
 -static void rk808_device_shutdown(void)
+static void rk805_device_shutdown(void)
 {
-ÂÂÂ int ret;
-ÂÂÂ struct rk808 *rk808 = i2c_get_clientdata(rk808_i2c_client);
-
-ÂÂÂ if (!rk808) {
-ÂÂÂÂÂÂÂ dev_warn(&rk808_i2c_client->dev,
-ÂÂÂÂÂÂÂÂÂÂÂÂ "have no rk808, so do nothing here\n");
-ÂÂÂÂÂÂÂ return;
-ÂÂÂ }
+ÂÂÂ rk808_update_bits(RK805_DEV_CTRL_REG, DEV_OFF);
+}
+static int rk805_restart_notify(struct notifier_block *this,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long mode, void *cmd)
+{
+ÂÂÂ rk808_update_bits(RK805_DEV_CTRL_REG, DEV_OFF_RST);
+ÂÂÂ return NOTIFY_DONE;
+}
 - ret = regmap_update_bits(rk808->regmap,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ RK808_DEVCTRL_REG,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ DEV_OFF_RST, DEV_OFF_RST);
-ÂÂÂ if (ret)
-ÂÂÂÂÂÂÂ dev_err(&rk808_i2c_client->dev, "power off error!\n");
+static void rk808_device_shutdown(void)
+{
+ÂÂÂ rk808_update_bits(RK808_DEVCTRL_REG, DEV_OFF_RST);
+}
+static int rk808_restart_notify(struct notifier_block *this,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long mode, void *cmd)
+{
+ÂÂÂ rk808_update_bits(RK808_DEVCTRL_REG, DEV_OFF);
+ÂÂÂ return NOTIFY_DONE;
 }
  static void rk818_device_shutdown(void)
 {
-ÂÂÂ int ret;
-ÂÂÂ struct rk808 *rk808 = i2c_get_clientdata(rk808_i2c_client);
+ÂÂÂ rk808_update_bits(RK818_DEVCTRL_REG, DEV_OFF_RST);
+}
+static int rk818_restart_notify(struct notifier_block *this,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned long mode, void *cmd)
+{
+ÂÂÂ rk808_update_bits(RK818_DEVCTRL_REG, DEV_OFF);
+ÂÂÂ return NOTIFY_DONE;
+}
 - if (!rk808) {
-ÂÂÂÂÂÂÂ dev_warn(&rk808_i2c_client->dev,
-ÂÂÂÂÂÂÂÂÂÂÂÂ "have no rk818, so do nothing here\n");
-ÂÂÂÂÂÂÂ return;
-ÂÂÂ }
+static struct notifier_block rk805_restart_handler = {
+ÂÂÂ .notifier_call = rk805_restart_notify,
+ÂÂÂ .priority = 196,
+};
 - ret = regmap_update_bits(rk808->regmap,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ RK818_DEVCTRL_REG,
-ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ DEV_OFF_RST, DEV_OFF_RST);
-ÂÂÂ if (ret)
-ÂÂÂÂÂÂÂ dev_err(&rk808_i2c_client->dev, "power off error!\n");
-}
+static struct notifier_block rk808_restart_handler = {
+ÂÂÂ .notifier_call = rk808_restart_notify,
+ÂÂÂ .priority = 196,
+};
+
+static struct notifier_block rk818_restart_handler = {
+ÂÂÂ .notifier_call = rk818_restart_notify,
+ÂÂÂ .priority = 196,
+};
  static const struct of_device_id rk808_of_match[] = {
ÂÂÂÂÂ { .compatible = "rockchip,rk805" },
@@ -476,6 +491,7 @@ static int rk808_probe(struct i2c_client *client,
ÂÂÂÂÂÂÂÂÂ cells = rk805s;
ÂÂÂÂÂÂÂÂÂ nr_cells = ARRAY_SIZE(rk805s);
ÂÂÂÂÂÂÂÂÂ pm_pwroff_fn = rk805_device_shutdown;
+ÂÂÂÂÂÂÂ rk808->nb = &rk805_restart_handler;
ÂÂÂÂÂÂÂÂÂ break;
ÂÂÂÂÂ case RK808_ID:
ÂÂÂÂÂÂÂÂÂ rk808->regmap_cfg = &rk808_regmap_config;
@@ -485,6 +501,7 @@ static int rk808_probe(struct i2c_client *client,
ÂÂÂÂÂÂÂÂÂ cells = rk808s;
ÂÂÂÂÂÂÂÂÂ nr_cells = ARRAY_SIZE(rk808s);
ÂÂÂÂÂÂÂÂÂ pm_pwroff_fn = rk808_device_shutdown;
+ÂÂÂÂÂÂÂ rk808->nb = &rk808_restart_handler;
ÂÂÂÂÂÂÂÂÂ break;
ÂÂÂÂÂ case RK818_ID:
ÂÂÂÂÂÂÂÂÂ rk808->regmap_cfg = &rk818_regmap_config;
@@ -494,6 +511,7 @@ static int rk808_probe(struct i2c_client *client,
ÂÂÂÂÂÂÂÂÂ cells = rk818s;
ÂÂÂÂÂÂÂÂÂ nr_cells = ARRAY_SIZE(rk818s);
ÂÂÂÂÂÂÂÂÂ pm_pwroff_fn = rk818_device_shutdown;
+ÂÂÂÂÂÂÂ rk808->nb = &rk818_restart_handler;
ÂÂÂÂÂÂÂÂÂ break;
ÂÂÂÂÂ default:
ÂÂÂÂÂÂÂÂÂ dev_err(&client->dev, "Unsupported RK8XX ID %lu\n",
@@ -546,11 +564,18 @@ static int rk808_probe(struct i2c_client *client,
 Â pm_off = of_property_read_bool(np,
ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "rockchip,system-power-controller");
-ÂÂÂ if (pm_off && !pm_power_off) {
+ÂÂÂ if (pm_off) {
ÂÂÂÂÂÂÂÂÂ rk808_i2c_client = client;
-ÂÂÂÂÂÂÂ pm_power_off = pm_pwroff_fn;
+ÂÂÂÂÂÂÂ if (!pm_power_off)
+ÂÂÂÂÂÂÂÂÂÂÂ pm_power_off = pm_pwroff_fn;
+ÂÂÂÂÂÂÂ if (rk808->nb) {
+ÂÂÂÂÂÂÂÂÂÂÂ ret = register_restart_handler(rk808->nb);
+ÂÂÂÂÂÂÂÂÂÂÂ if (ret)
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ dev_err(&client->dev,
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "cannot register restart handler, %d\n",
+ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ ret);
+ÂÂÂÂÂÂÂ }
ÂÂÂÂÂ }
-
ÂÂÂÂÂ return 0;
  err_irq:
@@ -564,6 +589,8 @@ static int rk808_remove(struct i2c_client *client)
 Â regmap_del_irq_chip(client->irq, rk808->irq_data);
ÂÂÂÂÂ pm_power_off = NULL;
+ÂÂÂ if (rk808->nb)
+ÂÂÂÂÂÂÂ unregister_restart_handler(rk808->nb);
 Â return 0;
 }
diff --git a/include/linux/mfd/rk808.h b/include/linux/mfd/rk808.h
index 338e0f6..9c26ca2 100644
--- a/include/linux/mfd/rk808.h
+++ b/include/linux/mfd/rk808.h
@@ -453,5 +453,6 @@ struct rk808 {
ÂÂÂÂÂ longÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ variant;
ÂÂÂÂÂ const struct regmap_configÂÂÂ *regmap_cfg;
ÂÂÂÂÂ const struct regmap_irq_chipÂÂÂ *regmap_irq_chip;
+ÂÂÂ struct notifier_blockÂÂÂÂÂÂÂ *nb;
 };
 #endif /* __LINUX_REGULATOR_RK808_H */