From e48bbb52a2aad8613291a9e4e757bbf995769015 Mon Sep 17 00:00:00 2001 From: "Claudiu.Beznea@microchip.com" Date: Tue, 21 Jan 2020 10:03:39 +0000 Subject: power: reset: at91-reset: handle nrst async for sam9x60 Handle NRST asynchronously for SAM9X60 to avoid problem with fast drop of VDDCORE on shutdown operations in the first 100 us after CPU is shutdown. Signed-off-by: Claudiu Beznea Signed-off-by: Sebastian Reichel --- drivers/power/reset/at91-reset.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/power') diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c index 537ccb180568..3ff9d93a5226 100644 --- a/drivers/power/reset/at91-reset.c +++ b/drivers/power/reset/at91-reset.c @@ -35,6 +35,7 @@ #define AT91_RSTC_MR 0x08 /* Reset Controller Mode Register */ #define AT91_RSTC_URSTEN BIT(0) /* User Reset Enable */ +#define AT91_RSTC_URSTASYNC BIT(2) /* User Reset Asynchronous Control */ #define AT91_RSTC_URSTIEN BIT(4) /* User Reset Interrupt Enable */ #define AT91_RSTC_ERSTL GENMASK(11, 8) /* External Reset Length */ @@ -228,6 +229,13 @@ static int __init at91_reset_probe(struct platform_device *pdev) platform_set_drvdata(pdev, reset); + if (of_device_is_compatible(pdev->dev.of_node, "microchip,sam9x60-rstc")) { + u32 val = readl(reset->rstc_base + AT91_RSTC_MR); + + writel(AT91_RSTC_KEY | AT91_RSTC_URSTASYNC | val, + reset->rstc_base + AT91_RSTC_MR); + } + ret = register_restart_handler(&reset->nb); if (ret) { clk_disable_unprepare(reset->sclk); -- cgit v1.2.3