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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/powerpc/platforms/powernv/opal-rtc.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/platforms/powernv/opal-rtc.c')
-rw-r--r-- | arch/powerpc/platforms/powernv/opal-rtc.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-rtc.c b/arch/powerpc/platforms/powernv/opal-rtc.c new file mode 100644 index 000000000..42ec642a3 --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-rtc.c @@ -0,0 +1,87 @@ +/* + * PowerNV Real Time Clock. + * + * Copyright 2011 IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + + +#include <linux/kernel.h> +#include <linux/time.h> +#include <linux/bcd.h> +#include <linux/rtc.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/of_platform.h> + +#include <asm/opal.h> +#include <asm/firmware.h> +#include <asm/machdep.h> + +static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm) +{ + tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) + + bcd2bin((y_m_d >> 16) & 0xff)) - 1900; + tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1; + tm->tm_mday = bcd2bin(y_m_d & 0xff); + tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff); + tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff); + tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff); + tm->tm_wday = -1; +} + +time64_t __init opal_get_boot_time(void) +{ + struct rtc_time tm; + u32 y_m_d; + u64 h_m_s_ms; + __be32 __y_m_d; + __be64 __h_m_s_ms; + long rc = OPAL_BUSY; + + if (!opal_check_token(OPAL_RTC_READ)) + return 0; + + while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { + rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms); + if (rc == OPAL_BUSY_EVENT) { + mdelay(OPAL_BUSY_DELAY_MS); + opal_poll_events(NULL); + } else if (rc == OPAL_BUSY) { + mdelay(OPAL_BUSY_DELAY_MS); + } + } + if (rc != OPAL_SUCCESS) + return 0; + + y_m_d = be32_to_cpu(__y_m_d); + h_m_s_ms = be64_to_cpu(__h_m_s_ms); + opal_to_tm(y_m_d, h_m_s_ms, &tm); + return rtc_tm_to_time64(&tm); +} + +static __init int opal_time_init(void) +{ + struct platform_device *pdev; + struct device_node *rtc; + + rtc = of_find_node_by_path("/ibm,opal/rtc"); + if (rtc) { + pdev = of_platform_device_create(rtc, "opal-rtc", NULL); + of_node_put(rtc); + } else { + if (opal_check_token(OPAL_RTC_READ) || + opal_check_token(OPAL_READ_TPO)) + pdev = platform_device_register_simple("opal-rtc", -1, + NULL, 0); + else + return -ENODEV; + } + + return PTR_ERR_OR_ZERO(pdev); +} +machine_subsys_initcall(powernv, opal_time_init); |