mips: octeon: dram.c: Add RAM driver support

This patch adds the initialization call for the Octeon RAM driver to
the Octeon platforms code. So if enabled via Kconfig, the DDR driver
will be called and the RAM will be configured and used. If the RAM
driver is not enabled, the L2 cache is still used as RAM.
Signed-off-by: NStefan Roese <sr@denx.de>

arch/mips/mach-octeon/dram.c

 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Copyright (C) Stefan Roese <sr@denx.de>
+ * Copyright (C) 2020 Stefan Roese <sr@denx.de>
  */
 
+#include <config.h>
 #include <dm.h>
 #include <ram.h>
 #include <asm/global_data.h>
 #include <linux/compat.h>
+#include <display_options.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define UBOOT_RAM_SIZE_MAX	0x10000000ULL
+
 int dram_init(void)
 {
-	/*
-	 * No DDR init yet -> run in L2 cache
-	 */
-	gd->ram_size = (4 << 20);
-	gd->bd->bi_dram[0].size = gd->ram_size;
-	gd->bd->bi_dram[1].size = 0;
+	if (IS_ENABLED(CONFIG_RAM_OCTEON)) {
+		struct ram_info ram;
+		struct udevice *dev;
+		int ret;
+
+		ret = uclass_get_device(UCLASS_RAM, 0, &dev);
+		if (ret) {
+			debug("DRAM init failed: %d\n", ret);
+			return ret;
+		}
+
+		ret = ram_get_info(dev, &ram);
+		if (ret) {
+			debug("Cannot get DRAM size: %d\n", ret);
+			return ret;
+		}
+
+		gd->ram_size = min_t(size_t, ram.size, UBOOT_RAM_SIZE_MAX);
+		debug("SDRAM base=%lx, size=%lx\n",
+		      (unsigned long)ram.base, (unsigned long)ram.size);
+	} else {
+		/*
+		 * No DDR init yet -> run in L2 cache
+		 */
+		gd->ram_size = (4 << 20);
+		gd->bd->bi_dram[0].size = gd->ram_size;
+		gd->bd->bi_dram[1].size = 0;
+	}
 
 	return 0;
 }
 
+void board_add_ram_info(int use_default)
+{
+	if (IS_ENABLED(CONFIG_RAM_OCTEON)) {
+		struct ram_info ram;
+		struct udevice *dev;
+		int ret;
+
+		ret = uclass_get_device(UCLASS_RAM, 0, &dev);
+		if (ret) {
+			debug("DRAM init failed: %d\n", ret);
+			return;
+		}
+
+		ret = ram_get_info(dev, &ram);
+		if (ret) {
+			debug("Cannot get DRAM size: %d\n", ret);
+			return;
+		}
+
+		printf(" (");
+		print_size(ram.size, " total)");
+	}
+}
+
 ulong board_get_usable_ram_top(ulong total_size)
 {
-	return gd->ram_top;
+	if (IS_ENABLED(CONFIG_RAM_OCTEON)) {
+		/* Map a maximum of 256MiB - return not size but address */
+		return CONFIG_SYS_SDRAM_BASE + min(gd->ram_size,
+						   UBOOT_RAM_SIZE_MAX);
+	} else {
+		return gd->ram_top;
+	}
 }