ARM: omap5: add hooks for cpu/SoC fdt fixups

Adds an fdt.c file in that defines the ft_cpu_setup() function,
which should be called from a board-specific ft_board_setup()).
This ft_cpu_setup() will currently do nothing for non-secure (GP)
devices	but contains pertinent updates for booting on secure (HS)
devices.

Update the omap5 Makefile to include the fdt.c in the build.

Signed-off-by: Daniel Allred <d-allred@ti.com>
Signed-off-by: Madan Srinivas <madans@ti.com>

Reviewed-by: Tom Rini <trini@konsulko.com>

arch/arm/cpu/armv7/omap5/Makefile

@@ -12,4 +12,5 @@ obj-y	+= sdram.o
 obj-y	+= prcm-regs.o
 obj-y	+= hw_data.o
 obj-y	+= abb.o
+obj-y	+= fdt.o
 obj-$(CONFIG_IODELAY_RECALIBRATION) += dra7xx_iodelay.o

arch/arm/cpu/armv7/omap5/fdt.c

@@ -0,0 +1,184 @@
+/*
+ * Copyright 2016 Texas Instruments, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <libfdt.h>
+#include <fdt_support.h>
+#include <malloc.h>
+
+#include <asm/omap_common.h>
+#include <asm/arch-omap5/sys_proto.h>
+
+#ifdef CONFIG_TI_SECURE_DEVICE
+
+/* Give zero values if not already defined */
+#ifndef TI_OMAP5_SECURE_BOOT_RESV_SRAM_SZ
+#define TI_OMAP5_SECURE_BOOT_RESV_SRAM_SZ (0)
+#endif
+#ifndef CONFIG_SECURE_RUNTIME_RESV_SRAM_SZ
+#define CONFIG_SECURE_RUNTIME_RESV_SRAM_SZ (0)
+#endif
+
+static u32 hs_irq_skip[] = {
+	8,	/* Secure violation reporting interrupt */
+	15,	/* One interrupt for SDMA by secure world */
+	118	/* One interrupt for Crypto DMA by secure world */
+};
+
+static int ft_hs_fixup_crossbar(void *fdt, bd_t *bd)
+{
+	const char *path;
+	int offs;
+	int ret;
+	int len, i, old_cnt, new_cnt;
+	u32 *temp;
+	const u32 *p_data;
+
+	/*
+	 * Increase the size of the fdt
+	 * so we have some breathing room
+	 */
+	ret = fdt_increase_size(fdt, 512);
+	if (ret < 0) {
+		printf("Could not increase size of device tree: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	/* Reserve IRQs that are used/needed by secure world */
+	path = "/ocp/crossbar";
+	offs = fdt_path_offset(fdt, path);
+	if (offs < 0) {
+		debug("Node %s not found.\n", path);
+		return 0;
+	}
+
+	/* Get current entries */
+	p_data = fdt_getprop(fdt, offs, "ti,irqs-skip", &len);
+	if (p_data)
+		old_cnt = len / sizeof(u32);
+	else
+		old_cnt = 0;
+
+	new_cnt = sizeof(hs_irq_skip) /
+				sizeof(hs_irq_skip[0]);
+
+	/* Create new/updated skip list for HS parts */
+	temp = malloc(sizeof(u32) * (old_cnt + new_cnt));
+	for (i = 0; i < new_cnt; i++)
+		temp[i] = cpu_to_fdt32(hs_irq_skip[i]);
+	for (i = 0; i < old_cnt; i++)
+		temp[i + new_cnt] = p_data[i];
+
+	/* Blow away old data and set new data */
+	fdt_delprop(fdt, offs, "ti,irqs-skip");
+	ret = fdt_setprop(fdt, offs, "ti,irqs-skip",
+			  temp,
+			  (old_cnt + new_cnt) * sizeof(u32));
+	free(temp);
+
+	/* Check if the update worked */
+	if (ret < 0) {
+		printf("Could not add ti,irqs-skip property to node %s: %s\n",
+		       path, fdt_strerror(ret));
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ft_hs_disable_rng(void *fdt, bd_t *bd)
+{
+	const char *path;
+	int offs;
+	int ret;
+
+	/* Make HW RNG reserved for secure world use */
+	path = "/ocp/rng";
+	offs = fdt_path_offset(fdt, path);
+	if (offs < 0) {
+		debug("Node %s not found.\n", path);
+		return 0;
+	}
+	ret = fdt_setprop_string(fdt, offs,
+				 "status", "disabled");
+	if (ret < 0) {
+		printf("Could not add status property to node %s: %s\n",
+		       path, fdt_strerror(ret));
+		return ret;
+	}
+	return 0;
+}
+
+#if ((TI_OMAP5_SECURE_BOOT_RESV_SRAM_SZ != 0) || \
+    (CONFIG_SECURE_RUNTIME_RESV_SRAM_SZ != 0))
+static int ft_hs_fixup_sram(void *fdt, bd_t *bd)
+{
+	const char *path;
+	int offs;
+	int ret;
+	u32 temp[2];
+
+	/*
+	 * Update SRAM reservations on secure devices. The OCMC RAM
+	 * is always reserved for secure use from the start of that
+	 * memory region
+	 */
+	path = "/ocp/ocmcram@40300000/sram-hs";
+	offs = fdt_path_offset(fdt, path);
+	if (offs < 0) {
+		debug("Node %s not found.\n", path);
+		return 0;
+	}
+
+	/* relative start offset */
+	temp[0] = cpu_to_fdt32(0);
+	/* reservation size */
+	temp[1] = cpu_to_fdt32(max(TI_OMAP5_SECURE_BOOT_RESV_SRAM_SZ,
+				   CONFIG_SECURE_RUNTIME_RESV_SRAM_SZ));
+	fdt_delprop(fdt, offs, "reg");
+	ret = fdt_setprop(fdt, offs, "reg", temp, 2 * sizeof(u32));
+	if (ret < 0) {
+		printf("Could not add reg property to node %s: %s\n",
+		       path, fdt_strerror(ret));
+		return ret;
+	}
+
+	return 0;
+}
+#else
+static int ft_hs_fixup_sram(void *fdt, bd_t *bd) { return 0; }
+#endif
+
+static void ft_hs_fixups(void *fdt, bd_t *bd)
+{
+	/* Check we are running on an HS/EMU device type */
+	if (GP_DEVICE != get_device_type()) {
+		if ((ft_hs_fixup_crossbar(fdt, bd) == 0) &&
+		    (ft_hs_disable_rng(fdt, bd) == 0) &&
+		    (ft_hs_fixup_sram(fdt, bd) == 0))
+			return;
+	} else {
+		printf("ERROR: Incorrect device type (GP) detected!");
+	}
+	/* Fixup failed or wrong device type */
+	hang();
+}
+#else
+static void ft_hs_fixups(void *fdt, bd_t *bd)
+{
+}
+#endif
+
+/*
+ * Place for general cpu/SoC FDT fixups. Board specific
+ * fixups should remain in the board files which is where
+ * this function should be called from.
+ */
+void ft_cpu_setup(void *fdt, bd_t *bd)
+{
+	ft_hs_fixups(fdt, bd);
+}