diff options
Diffstat (limited to 'cpu')
| -rw-r--r-- | cpu/arm_cortexa8/mx6/generic.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/cpu/arm_cortexa8/mx6/generic.c b/cpu/arm_cortexa8/mx6/generic.c index ac7fa6e..789db98 100644 --- a/cpu/arm_cortexa8/mx6/generic.c +++ b/cpu/arm_cortexa8/mx6/generic.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2010-2013 Freescale Semiconductor, Inc. + * Copyright (C) 2010-2014 Freescale Semiconductor, Inc. * * See file CREDITS for list of people who contributed to this * project. @@ -916,8 +916,6 @@ static inline int read_cpu_temperature(void) the temperature, we will power on/down the anadig module*/ writel(BM_ANADIG_TEMPSENSE0_POWER_DOWN, ANATOP_BASE_ADDR + HW_ANADIG_TEMPSENSE0_CLR); - writel(BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF, - ANATOP_BASE_ADDR + HW_ANADIG_ANA_MISC0_SET); /* write measure freq */ reg = readl(ANATOP_BASE_ADDR + HW_ANADIG_TEMPSENSE1); @@ -953,8 +951,6 @@ static inline int read_cpu_temperature(void) /* power down anatop thermal sensor */ writel(BM_ANADIG_TEMPSENSE0_POWER_DOWN, ANATOP_BASE_ADDR + HW_ANADIG_TEMPSENSE0_SET); - writel(BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF, - ANATOP_BASE_ADDR + HW_ANADIG_ANA_MISC0_CLR); return temperature; @@ -1031,6 +1027,22 @@ int cpu_eth_init(bd_t *bis) return rc; } +static void init_bandgap(void) +{ + /* + * Ensure the bandgap has stabilized. + */ + while (!(readl(ANATOP_BASE_ADDR + HW_ANADIG_ANA_MISC0) & 0x80)) + ; + /* + * For best noise performance of the analog blocks using the + * outputs of the bandgap, the reftop_selfbias_off bit should + * be set. + */ + writel(BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF, + ANATOP_BASE_ADDR + HW_ANADIG_ANA_MISC0_SET); +} + #if defined(CONFIG_ARCH_CPU_INIT) int arch_cpu_init(void) { @@ -1039,6 +1051,13 @@ int arch_cpu_init(void) /* Clear MMDC channel mask */ writel(0, CCM_BASE_ADDR + 0x4); + /* + * Disable self-bias circuit in the analog bandap. + * The self-bias circuit is used by the bandgap during startup. + * This bit should be set after the bandgap has initialized. + */ + init_bandgap(); + /* Due to hardware limitation, on MX6Q we need to gate/ungate all PFDs * to make sure PFD is working right, otherwise, PFDs may * not output clock after reset, MX6DL and MX6SL have added 396M pfd |