pinctrl: cherryview: Mask all interrupts on Intel_Strago based systems

Guenter Roeck reported an interrupt storm on a prototype system which is
based on Cyan Chromebook. The root cause turned out to be a incorrectly
configured pin that triggers spurious interrupts. This will be fixed in
coreboot but currently we need to prevent the interrupt storm from
happening by masking all interrupts (but not GPEs) on those systems.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=197953
Fixes: bcb48cca23 ("pinctrl: cherryview: Do not mask all interrupts in probe")
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/intel/pinctrl-cherryview.c

@@ -1620,6 +1620,22 @@ static int chv_gpio_probe(struct chv_pinctrl *pctrl, int irq)
 			clear_bit(i, chip->irq.valid_mask);
 	}
 
+	/*
+	 * The same set of machines in chv_no_valid_mask[] have incorrectly
+	 * configured GPIOs that generate spurious interrupts so we use
+	 * this same list to apply another quirk for them.
+	 *
+	 * See also https://bugzilla.kernel.org/show_bug.cgi?id=197953.
+	 */
+	if (!need_valid_mask) {
+		/*
+		 * Mask all interrupts the community is able to generate
+		 * but leave the ones that can only generate GPEs unmasked.
+		 */
+		chv_writel(GENMASK(31, pctrl->community->nirqs),
+			   pctrl->regs + CHV_INTMASK);
+	}
+
 	/* Clear all interrupts */
 	chv_writel(0xffff, pctrl->regs + CHV_INTSTAT);