[U-Boot] [PATCH 2/2] board/b4qds: VID support
Shaveta Leekha
shaveta at freescale.com
Fri Apr 11 10:42:40 CEST 2014
The fuse status register provides the values from on-chip
voltage ID efuses programmed at the factory.
These values define the voltage requirements for
the chip. u-boot reads FUSESR and translates the values
into the appropriate commands to set the voltage output
value of an external voltage regulator.
B4860QDS has a PowerOne ZM7300 programmable digital Power
Manager which is programmed as per the value read from
the fuses.
Reference for this code is taken from t4qds VID implementation.
Signed-off-by: Shaveta Leekha <shaveta at freescale.com>
Signed-off-by: Poonam Aggrwal <poonam.aggrwal at freescale.com>
---
board/freescale/b4860qds/b4860qds.c | 240 +++++++++++++++++++++++++++++++++++
include/configs/B4860QDS.h | 11 ++
2 files changed, 251 insertions(+), 0 deletions(-)
diff --git a/board/freescale/b4860qds/b4860qds.c b/board/freescale/b4860qds/b4860qds.c
index d9c88a0..b2d5378 100644
--- a/board/freescale/b4860qds/b4860qds.c
+++ b/board/freescale/b4860qds/b4860qds.c
@@ -23,6 +23,7 @@
#include "../common/qixis.h"
#include "../common/vsc3316_3308.h"
#include "../common/idt8t49n222a_serdes_clk.h"
+#include "../common/zm7300.h"
#include "b4860qds.h"
#include "b4860qds_qixis.h"
#include "b4860qds_crossbar_con.h"
@@ -94,6 +95,238 @@ int select_i2c_ch_pca(u8 ch)
return 0;
}
+/*
+ * read_voltage from sensor on I2C bus
+ * We use average of 4 readings, waiting for 532us befor another reading
+ */
+#define WAIT_FOR_ADC 532 /* wait for 532 microseconds for ADC */
+#define NUM_READINGS 4 /* prefer to be power of 2 for efficiency */
+
+static inline int read_voltage(void)
+{
+ int i, ret, voltage_read = 0;
+ u16 vol_mon;
+
+ for (i = 0; i < NUM_READINGS; i++) {
+ ret = i2c_read(I2C_VOL_MONITOR_ADDR,
+ I2C_VOL_MONITOR_BUS_V_OFFSET, 1, (void *)&vol_mon, 2);
+ if (ret) {
+ printf("VID: failed to read core voltage\n");
+ return ret;
+ }
+ if (vol_mon & I2C_VOL_MONITOR_BUS_V_OVF) {
+ printf("VID: Core voltage sensor error\n");
+ return -1;
+ }
+ debug("VID: bus voltage reads 0x%04x\n", vol_mon);
+ /* LSB = 4mv */
+ voltage_read += (vol_mon >> I2C_VOL_MONITOR_BUS_V_SHIFT) * 4;
+ udelay(WAIT_FOR_ADC);
+ }
+ /* calculate the average */
+ voltage_read /= NUM_READINGS;
+
+ return voltage_read;
+}
+
+static int adjust_vdd(ulong vdd_override)
+{
+ int re_enable = disable_interrupts();
+ ccsr_gur_t __iomem *gur =
+ (void __iomem *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
+ u32 fusesr;
+ u8 vid;
+ int vdd_target, vdd_last;
+ int existing_voltage, temp_voltage, voltage; /* all in 1/10 mV */
+ int ret;
+ unsigned int orig_i2c_speed;
+ unsigned long vdd_string_override;
+ char *vdd_string;
+ static const uint16_t vdd[32] = {
+ 0, /* unused */
+ 9875, /* 0.9875V */
+ 9750,
+ 9625,
+ 9500,
+ 9375,
+ 9250,
+ 9125,
+ 9000,
+ 8875,
+ 8750,
+ 8625,
+ 8500,
+ 8375,
+ 8250,
+ 8125,
+ 10000, /* 1.0000V */
+ 10125,
+ 10250,
+ 10375,
+ 10500,
+ 10625,
+ 10750,
+ 10875,
+ 11000,
+ 0, /* reserved */
+ };
+ struct vdd_drive {
+ u8 vid;
+ unsigned voltage;
+ };
+
+ ret = select_i2c_ch_pca(I2C_MUX_CH_VOL_MONITOR);
+ if (ret) {
+ printf("VID: I2c failed to switch channel\n");
+ ret = -1;
+ goto exit;
+ }
+
+ /* get the voltage ID from fuse status register */
+ fusesr = in_be32(&gur->dcfg_fusesr);
+ vid = (fusesr >> FSL_CORENET_DCFG_FUSESR_VID_SHIFT) &
+ FSL_CORENET_DCFG_FUSESR_VID_MASK;
+ if (vid == FSL_CORENET_DCFG_FUSESR_VID_MASK) {
+ vid = (fusesr >> FSL_CORENET_DCFG_FUSESR_ALTVID_SHIFT) &
+ FSL_CORENET_DCFG_FUSESR_ALTVID_MASK;
+ }
+ vdd_target = vdd[vid];
+ debug("VID:Reading from from fuse,vid=%x vdd is %dmV\n",
+ vid, vdd_target/10);
+
+ /* check override variable for overriding VDD */
+ vdd_string = getenv("b4qds_vdd_mv");
+ if (vdd_override == 0 && vdd_string &&
+ !strict_strtoul(vdd_string, 10, &vdd_string_override))
+ vdd_override = vdd_string_override;
+ if (vdd_override >= 819 && vdd_override <= 1212) {
+ vdd_target = vdd_override * 10; /* convert to 1/10 mV */
+ debug("VDD override is %lu\n", vdd_override);
+ } else if (vdd_override != 0) {
+ printf("Invalid value.\n");
+ }
+
+ if (vdd_target == 0) {
+ printf("VID: VID not used\n");
+ ret = 0;
+ goto exit;
+ }
+
+ /*
+ * Read voltage monitor to check real voltage.
+ * Voltage monitor LSB is 4mv.
+ */
+ vdd_last = read_voltage();
+ if (vdd_last < 0) {
+ printf("VID: abort VID adjustment\n");
+ ret = -1;
+ goto exit;
+ }
+
+ debug("VID: Core voltage is at %d mV\n", vdd_last);
+ ret = select_i2c_ch_pca(I2C_MUX_CH_DPM);
+ if (ret) {
+ printf("VID: I2c failed to switch channel to DPM\n");
+ ret = -1;
+ goto exit;
+ }
+
+ /* Round up to the value of step of Voltage regulator */
+ voltage = roundup(vdd_target, ZM_STEP);
+ debug("VID: rounded up voltage = %d\n", voltage);
+
+ /* lower the speed to 100kHz to access ZM7300 device */
+ debug("VID: Setting bus speed to 100KHz if not already set\n");
+ orig_i2c_speed = i2c_get_bus_speed();
+ if (orig_i2c_speed != 100000)
+ i2c_set_bus_speed(100000);
+
+ /* Read the existing level on board, if equal to requsted one,
+ no need to re-set */
+ existing_voltage = zm_read_voltage();
+
+ /* allowing the voltage difference of one step 0.0125V acceptable */
+ if ((existing_voltage >= voltage) &&
+ (existing_voltage < (voltage + ZM_STEP))) {
+ debug("VID: voltage already set as requested,returning\n");
+ ret = existing_voltage;
+ goto out;
+ }
+ debug("VID: Changing voltage for board from %dmV to %dmV\n",
+ existing_voltage/10, voltage/10);
+
+ if (zm_disable_wp() < 0) {
+ ret = -1;
+ goto out;
+ }
+ /* Change Voltage: the change is done through all the steps in the
+ way, to avoid reset to the board due to power good signal fail
+ in big voltage change gap jump.
+ */
+ if (existing_voltage > voltage) {
+ temp_voltage = existing_voltage - ZM_STEP;
+ while (temp_voltage >= voltage) {
+ ret = zm_write_voltage(temp_voltage);
+ if (ret == temp_voltage) {
+ temp_voltage -= ZM_STEP;
+ } else {
+ /* ZM7300 device failed to set
+ * the voltage */
+ printf
+ ("VID:Stepping down vol failed:%dmV\n",
+ temp_voltage/10);
+ ret = -1;
+ goto out;
+ }
+ }
+ } else {
+ temp_voltage = existing_voltage + ZM_STEP;
+ while (temp_voltage < (voltage + ZM_STEP)) {
+ ret = zm_write_voltage(temp_voltage);
+ if (ret == temp_voltage) {
+ temp_voltage += ZM_STEP;
+ } else {
+ /* ZM7300 device failed to set
+ * the voltage */
+ printf
+ ("VID:Stepping up vol failed:%dmV\n",
+ temp_voltage/10);
+ ret = -1;
+ goto out;
+ }
+ }
+ }
+
+ if (zm_enable_wp() < 0)
+ ret = -1;
+
+ /* restore the speed to 400kHz */
+out: debug("VID: Restore the I2C bus speed to %dKHz\n",
+ orig_i2c_speed/1000);
+ i2c_set_bus_speed(orig_i2c_speed);
+ if (ret < 0)
+ goto exit;
+
+ ret = select_i2c_ch_pca(I2C_MUX_CH_VOL_MONITOR);
+ if (ret) {
+ printf("VID: I2c failed to switch channel\n");
+ ret = -1;
+ goto exit;
+ }
+ vdd_last = read_voltage();
+ select_i2c_ch_pca(I2C_CH_DEFAULT);
+
+ if (vdd_last > 0)
+ printf("VID: Core voltage %d mV\n", vdd_last);
+ else
+ ret = -1;
+
+exit:
+ if (re_enable)
+ enable_interrupts();
+ return ret;
+}
+
int configure_vsc3316_3308(void)
{
ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
@@ -697,6 +930,13 @@ int board_early_init_r(void)
#ifdef CONFIG_SYS_DPAA_QBMAN
setup_portals();
#endif
+ /*
+ * Adjust core voltage according to voltage ID
+ * This function changes I2C mux to channel 2.
+ */
+ if (adjust_vdd(0) < 0)
+ printf("Warning: Adjusting core voltage failed\n");
+
/* SerDes1 refclks need to be set again, as default clks
* are not suitable for CPRI and onboard SGMIIs to work
* simultaneously.
diff --git a/include/configs/B4860QDS.h b/include/configs/B4860QDS.h
index b248302..2357f96 100644
--- a/include/configs/B4860QDS.h
+++ b/include/configs/B4860QDS.h
@@ -82,6 +82,17 @@
#define IDT_SERDES1_ADDRESS 0x6E
#define IDT_SERDES2_ADDRESS 0x6C
+/* Voltage monitor on channel 2*/
+#define I2C_MUX_CH_VOL_MONITOR 0xa
+#define I2C_VOL_MONITOR_ADDR 0x40
+#define I2C_VOL_MONITOR_BUS_V_OFFSET 0x2
+#define I2C_VOL_MONITOR_BUS_V_OVF 0x1
+#define I2C_VOL_MONITOR_BUS_V_SHIFT 3
+
+#define CONFIG_ZM7300
+#define I2C_MUX_CH_DPM 0xa
+#define I2C_DPM_ADDR 0x28
+
#define CONFIG_ENV_OVERWRITE
#ifdef CONFIG_SYS_NO_FLASH
--
1.7.6.GIT
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