Kuan-Wei ChiuandTom Rini
47e9c542ee
goldfish_rtc_of_to_plat() currently returns success even when dev_read_addr() fails to find a valid address. This leaves plat->reg unset (or 0) and defers the failure to probe(). Return -EINVAL immediately when the address is FDT_ADDR_T_NONE so the failure is reported at the of_to_plat stage where it belongs. This aligns the driver with the recent fix introduced in the goldfish serial driver by Naveen Kumar Chaudhary. [1] Link: https://lore.kernel.org/u-boot/vgwnt6mnls3lf3zdm6mz5siztzkvppte4ykszbvifjzukvmksf@maaxe5agqpim/ [1] Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
127 lines
2.7 KiB
C
127 lines
2.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright 2023, Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
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*
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* This driver supports the Google Goldfish virtual platform RTC device.
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* The device is provided by the RISC-V virt machine in QEMU. It exposes
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* a 64-bit nanosecond timer via two memory-mapped 32-bit registers.
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*/
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#include <div64.h>
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#include <dm.h>
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#include <goldfish_rtc.h>
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#include <mapmem.h>
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#include <rtc.h>
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#include <linux/io.h>
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/**
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* struct goldfish_rtc - private data for RTC driver
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*/
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struct goldfish_rtc {
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/**
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* @base: base address for register file
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*/
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void __iomem *base;
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/**
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* @isdst: daylight saving time
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*/
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int isdst;
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};
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/* Register offsets */
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#define GOLDFISH_TIME_LOW 0x00
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#define GOLDFISH_TIME_HIGH 0x04
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static int goldfish_rtc_get(struct udevice *dev, struct rtc_time *time)
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{
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struct goldfish_rtc *priv = dev_get_priv(dev);
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void __iomem *base = priv->base;
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u64 time_high;
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u64 time_low;
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u64 now;
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time_low = __raw_readl(base + GOLDFISH_TIME_LOW);
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time_high = __raw_readl(base + GOLDFISH_TIME_HIGH);
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now = (time_high << 32) | time_low;
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do_div(now, 1000000000U);
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rtc_to_tm(now, time);
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time->tm_isdst = priv->isdst;
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return 0;
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}
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static int goldfish_rtc_set(struct udevice *dev, const struct rtc_time *time)
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{
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struct goldfish_rtc *priv = dev_get_priv(dev);
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void __iomem *base = priv->base;
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u64 now;
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if (time->tm_year < 1970)
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return -EINVAL;
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now = rtc_mktime(time) * 1000000000ULL;
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__raw_writel(now >> 32, base + GOLDFISH_TIME_HIGH);
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__raw_writel(now, base + GOLDFISH_TIME_LOW);
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if (time->tm_isdst > 0)
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priv->isdst = 1;
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else if (time->tm_isdst < 0)
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priv->isdst = -1;
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else
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priv->isdst = 0;
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return 0;
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}
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static int goldfish_rtc_of_to_plat(struct udevice *dev)
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{
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struct goldfish_rtc_plat *plat = dev_get_plat(dev);
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fdt_addr_t addr;
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plat->reg = 0;
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addr = dev_read_addr(dev);
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if (addr == FDT_ADDR_T_NONE)
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return -EINVAL;
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plat->reg = addr;
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return 0;
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}
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static int goldfish_rtc_probe(struct udevice *dev)
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{
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struct goldfish_rtc_plat *plat = dev_get_plat(dev);
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struct goldfish_rtc *priv = dev_get_priv(dev);
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if (!plat->reg)
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return -EINVAL;
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priv->base = map_sysmem(plat->reg, 0x20);
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return 0;
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}
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static const struct rtc_ops goldfish_rtc_ops = {
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.get = goldfish_rtc_get,
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.set = goldfish_rtc_set,
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};
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static const struct udevice_id goldfish_rtc_of_match[] = {
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{ .compatible = "google,goldfish-rtc", },
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{},
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};
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U_BOOT_DRIVER(rtc_goldfish) = {
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.name = "rtc_goldfish",
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.id = UCLASS_RTC,
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.ops = &goldfish_rtc_ops,
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.probe = goldfish_rtc_probe,
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.of_match = goldfish_rtc_of_match,
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.of_to_plat = goldfish_rtc_of_to_plat,
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.plat_auto = sizeof(struct goldfish_rtc_plat),
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.priv_auto = sizeof(struct goldfish_rtc),
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};
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