[PATCH] linux: arch: define aspeed SOC IO mapping

From: Christian Svensson <bluecmd@google.com>
To: openbmc@lists.ozlabs.org
Cc: blue@cmd.nu, joel@jms.id.au, andrew@aj.id.au, clg@kaod.org,
	 Christian Svensson <bluecmd@google.com>
Subject: [PATCH] linux: arch: define aspeed SOC IO mapping
Date: Mon, 12 Nov 2018 15:25:42 +0100	[thread overview]
Message-ID: <20181112142541.166609-1-bluecmd@google.com> (raw)

Without this IO mapping early printk will simply not work after the
paging and MMU has been setup.

This patch maps all the whole 0x1e600000 IO space to 0xfe600000.

Signed-off-by: Christian Svensson <bluecmd@google.com>
---
 arch/arm/Makefile                 |  1 +
 arch/arm/mach-aspeed/Makefile     |  1 +
 arch/arm/mach-aspeed/aspeed_soc.c | 47 +++++++++++++++++++++++++++++++
 arch/arm/mach-aspeed/iomap.h      | 17 +++++++++++
 4 files changed, 66 insertions(+)
 create mode 100644 arch/arm/mach-aspeed/Makefile
 create mode 100644 arch/arm/mach-aspeed/aspeed_soc.c
 create mode 100644 arch/arm/mach-aspeed/iomap.h

diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index fc26c3d7b9b6..f0e3ca392f8c 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -159,6 +159,7 @@ textofs-$(CONFIG_ARCH_AXXIA) := 0x00308000
 machine-$(CONFIG_ARCH_ACTIONS)		+= actions
 machine-$(CONFIG_ARCH_ALPINE)		+= alpine
 machine-$(CONFIG_ARCH_ARTPEC)		+= artpec
+machine-$(CONFIG_ARCH_ASPEED)		+= aspeed
 machine-$(CONFIG_ARCH_AT91)		+= at91
 machine-$(CONFIG_ARCH_AXXIA)		+= axxia
 machine-$(CONFIG_ARCH_BCM)		+= bcm
diff --git a/arch/arm/mach-aspeed/Makefile b/arch/arm/mach-aspeed/Makefile
new file mode 100644
index 000000000000..426952d47cc3
--- /dev/null
+++ b/arch/arm/mach-aspeed/Makefile
@@ -0,0 +1 @@
+obj-y := aspeed_soc.o
diff --git a/arch/arm/mach-aspeed/aspeed_soc.c b/arch/arm/mach-aspeed/aspeed_soc.c
new file mode 100644
index 000000000000..187276c2813d
--- /dev/null
+++ b/arch/arm/mach-aspeed/aspeed_soc.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2018 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/of_platform.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#include "iomap.h"
+
+// This is needed for e.g. earlyprintk
+static struct map_desc io_desc[] __initdata = {
+	{
+		.virtual = AST_IO_VIRT,
+		.pfn = __phys_to_pfn(AST_IO_PHYS),
+		.length = AST_IO_SIZE,
+		.type = MT_DEVICE
+	}
+};
+
+static void __init aspeed_map_io(void)
+{
+	iotable_init(io_desc, ARRAY_SIZE(io_desc));
+}
+
+static const char * const aspeed_compat[] = {
+	"aspeed,ast2400",
+	"aspeed,ast2500",
+	NULL
+};
+
+DT_MACHINE_START(ASPEED_DT, "Aspeed SoC")
+	.map_io = aspeed_map_io,
+	.dt_compat = aspeed_compat,
+MACHINE_END
diff --git a/arch/arm/mach-aspeed/iomap.h b/arch/arm/mach-aspeed/iomap.h
new file mode 100644
index 000000000000..7ea5276f3892
--- /dev/null
+++ b/arch/arm/mach-aspeed/iomap.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2018 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define AST_IO_PHYS 0x1e600000
+#define AST_IO_VIRT 0xfe600000
+#define AST_IO_SIZE 0x00200000
-- 
2.19.1.930.g4563a0d9d0-goog
