soc/tegra: pmc: Configure core power request polarity

This patch configures polarity of the core power request signal
in PMC control register based on the device tree property.

PMC asserts and de-asserts power request signal based on it polarity
when it need to power-up and power-down the core rail during SC7.
Reviewed-by: NDmitry Osipenko <digetx@gmail.com>
Signed-off-by: NSowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>

drivers/soc/tegra/pmc.c

@@ -56,6 +56,7 @@
 #define  PMC_CNTRL_SIDE_EFFECT_LP0	BIT(14) /* LP0 when CPU pwr gated */
 #define  PMC_CNTRL_SYSCLK_OE		BIT(11) /* system clock enable */
 #define  PMC_CNTRL_SYSCLK_POLARITY	BIT(10) /* sys clk polarity */
+#define  PMC_CNTRL_PWRREQ_POLARITY	BIT(8)
 #define  PMC_CNTRL_MAIN_RST		BIT(4)
 
 #define PMC_WAKE_MASK			0x0c
@@ -2316,6 +2317,11 @@ static void tegra20_pmc_init(struct tegra_pmc *pmc)
 	else
 		value |= PMC_CNTRL_SYSCLK_POLARITY;
 
+	if (pmc->corereq_high)
+		value &= ~PMC_CNTRL_PWRREQ_POLARITY;
+	else
+		value |= PMC_CNTRL_PWRREQ_POLARITY;
+
 	/* configure the output polarity while the request is tristated */
 	tegra_pmc_writel(pmc, value, PMC_CNTRL);