ARM: tegra: Support TZ-only access to PMC

Some devices may restrict access to the PMC to TrustZone software only.
Non-TZ software can detect this and use SMC calls to the firmware that
runs in the TrustZone to perform accesses to PMC registers.

Note that this also fixes reset_cpu() and the enterrcm command on
Tegra186 where they were previously trying to access the PMC at a wrong
physical address.

Based on work by Kalyani Chidambaram <kalyanic@nvidia.com> and Tom
Warren <twarren@nvidia.com>.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/mach-tegra/cpu.c b/arch/arm/mach-tegra/cpu.c
index 1b6ad07..3d14076 100644
--- a/arch/arm/mach-tegra/cpu.c
+++ b/arch/arm/mach-tegra/cpu.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) 2010-2015, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2010-2019, NVIDIA CORPORATION.  All rights reserved.
  */
 
 #include <common.h>
@@ -299,21 +299,19 @@
 
 static int is_cpu_powered(void)
 {
-	struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
-
-	return (readl(&pmc->pmc_pwrgate_status) & CPU_PWRED) ? 1 : 0;
+	return (tegra_pmc_readl(offsetof(struct pmc_ctlr,
+				pmc_pwrgate_status)) & CPU_PWRED) ? 1 : 0;
 }
 
 static void remove_cpu_io_clamps(void)
 {
-	struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
 	u32 reg;
 	debug("%s entry\n", __func__);
 
 	/* Remove the clamps on the CPU I/O signals */
-	reg = readl(&pmc->pmc_remove_clamping);
+	reg = tegra_pmc_readl(offsetof(struct pmc_ctlr, pmc_remove_clamping));
 	reg |= CPU_CLMP;
-	writel(reg, &pmc->pmc_remove_clamping);
+	tegra_pmc_writel(reg, offsetof(struct pmc_ctlr, pmc_remove_clamping));
 
 	/* Give I/O signals time to stabilize */
 	udelay(IO_STABILIZATION_DELAY);
@@ -321,17 +319,19 @@
 
 void powerup_cpu(void)
 {
-	struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
 	u32 reg;
 	int timeout = IO_STABILIZATION_DELAY;
 	debug("%s entry\n", __func__);
 
 	if (!is_cpu_powered()) {
 		/* Toggle the CPU power state (OFF -> ON) */
-		reg = readl(&pmc->pmc_pwrgate_toggle);
+		reg = tegra_pmc_readl(offsetof(struct pmc_ctlr,
+				      pmc_pwrgate_toggle));
 		reg &= PARTID_CP;
 		reg |= START_CP;
-		writel(reg, &pmc->pmc_pwrgate_toggle);
+		tegra_pmc_writel(reg,
+				 offsetof(struct pmc_ctlr,
+				 pmc_pwrgate_toggle));
 
 		/* Wait for the power to come up */
 		while (!is_cpu_powered()) {