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@freescale.com Signed-off-by: Poonam Aggrwal poonam.aggrwal@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