Commit 473c5b29 authored by Sami Mujawar's avatar Sami Mujawar Committed by Will Deacon
Browse files

rtc: Initialize the Register D for MC146818 RTC



Some software drivers check the VRT bit (BIT7) of Register D before
using the MC146818 RTC. Initialized the VRT bit in rtc__init() to
indicate that the RAM and time contents are valid.
Signed-off-by: Sami Mujawar's avatarSami Mujawar <sami.mujawar@arm.com>
Signed-off-by: default avatarJulien Thierry <julien.thierry@arm.com>
Reviewed-by: Andre Przywara's avatarAndre Przywara <andre.przywara@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 5ae841d1
......@@ -25,6 +25,11 @@
#define RTC_REG_C 0x0C
#define RTC_REG_D 0x0D
/*
* Register D Bits
*/
#define RTC_REG_D_VRT (1 << 7)
struct rtc_device {
u8 cmos_idx;
u8 cmos_data[128];
......@@ -140,6 +145,9 @@ int rtc__init(struct kvm *kvm)
return r;
}
/* Set the VRT bit in Register D to indicate valid RAM and time */
rtc.cmos_data[RTC_REG_D] = RTC_REG_D_VRT;
return r;
}
dev_init(rtc__init);
......
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