diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/cpu/armv7/mx6/soc.c | 24 | ||||
| -rw-r--r-- | arch/arm/include/asm/arch-mx6/crm_regs.h | 2 |
2 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c index e599a12..df4e824 100644 --- a/arch/arm/cpu/armv7/mx6/soc.c +++ b/arch/arm/cpu/armv7/mx6/soc.c @@ -255,6 +255,23 @@ static void clear_mmdc_ch_mask(void) writel(0, &mxc_ccm->ccdr); } +static void init_bandgap(void) +{ + struct anatop_regs *anatop = (struct anatop_regs *)ANATOP_BASE_ADDR; + /* + * Ensure the bandgap has stabilized. + */ + while (!(readl(&anatop->ana_misc0) & 0x80)) + ; + /* + * For best noise performance of the analog blocks using the + * outputs of the bandgap, the reftop_selfbiasoff bit should + * be set. + */ + writel(BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_set); +} + + #ifdef CONFIG_MX6SL static void set_preclk_from_osc(void) { @@ -275,6 +292,13 @@ int arch_cpu_init(void) clear_mmdc_ch_mask(); /* + * 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(); + + /* * When low freq boot is enabled, ROM will not set AHB * freq, so we need to ensure AHB freq is 132MHz in such * scenario. diff --git a/arch/arm/include/asm/arch-mx6/crm_regs.h b/arch/arm/include/asm/arch-mx6/crm_regs.h index 39f3c07..0592ce0 100644 --- a/arch/arm/include/asm/arch-mx6/crm_regs.h +++ b/arch/arm/include/asm/arch-mx6/crm_regs.h @@ -1063,4 +1063,6 @@ struct mxc_ccm_reg { #define BF_ANADIG_PFD_528_PFD0_FRAC(v) \ (((v) << 0) & BM_ANADIG_PFD_528_PFD0_FRAC) +#define BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF 0x00000008 + #endif /*__ARCH_ARM_MACH_MX6_CCM_REGS_H__ */ |