[PATCH v4 5/5] zynq: move static peripheral mappings

From: Josh Cartwright <josh.cartwright@ni.com>
To: arm@kernel.org, Arnd Bergmann <arnd@arndb.de>
Cc: linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	John Linn <john.linn@xilinx.com>,
	Nick Bowler <nbowler@elliptictech.com>,
	Michal Simek <michal.simek@xilinx.com>
Subject: [PATCH v4 5/5] zynq: move static peripheral mappings
Date: Sun, 21 Oct 2012 21:15:37 -0500	[thread overview]
Message-ID: <7a663040dc05b79262d7bd8bf8224ca49eb00162.1351466765.git.josh.cartwright@ni.com> (raw)
In-Reply-To: <cover.1351466765.git.josh.cartwright@ni.com>

Shifting them up into the vmalloc region prevents the following warning,
when booting a zynq qemu target with more than 512mb of RAM:

  BUG: mapping for 0xe0000000 at 0xe0000000 out of vmalloc space

In addition, it allows for reuse of these mappings when the proper
drivers issue requests via ioremap().

There are currently unknown issues with the early uart mapping.  For
now, the uart will be mapped to a known working address.

Signed-off-by: Josh Cartwright <josh.cartwright@ni.com>
Cc: John Linn <john.linn@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/arm/mach-zynq/common.c                |  6 +++---
 arch/arm/mach-zynq/include/mach/zynq_soc.h | 25 +++++++++++++++----------
 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/arch/arm/mach-zynq/common.c b/arch/arm/mach-zynq/common.c
index ba48f06..ba8d14f 100644
--- a/arch/arm/mach-zynq/common.c
+++ b/arch/arm/mach-zynq/common.c
@@ -73,12 +73,12 @@ static struct map_desc io_desc[] __initdata = {
 	{
 		.virtual	= TTC0_VIRT,
 		.pfn		= __phys_to_pfn(TTC0_PHYS),
-		.length		= SZ_4K,
+		.length		= TTC0_SIZE,
 		.type		= MT_DEVICE,
 	}, {
 		.virtual	= SCU_PERIPH_VIRT,
 		.pfn		= __phys_to_pfn(SCU_PERIPH_PHYS),
-		.length		= SZ_8K,
+		.length		= SCU_PERIPH_SIZE,
 		.type		= MT_DEVICE,
 	},
 
@@ -86,7 +86,7 @@ static struct map_desc io_desc[] __initdata = {
 	{
 		.virtual	= UART0_VIRT,
 		.pfn		= __phys_to_pfn(UART0_PHYS),
-		.length		= SZ_4K,
+		.length		= UART0_SIZE,
 		.type		= MT_DEVICE,
 	},
 #endif
diff --git a/arch/arm/mach-zynq/include/mach/zynq_soc.h b/arch/arm/mach-zynq/include/mach/zynq_soc.h
index 218283a..1b8bf0e 100644
--- a/arch/arm/mach-zynq/include/mach/zynq_soc.h
+++ b/arch/arm/mach-zynq/include/mach/zynq_soc.h
@@ -15,27 +15,32 @@
 #ifndef __MACH_XILINX_SOC_H__
 #define __MACH_XILINX_SOC_H__
 
+#include <asm/pgtable.h>
+
 #define PERIPHERAL_CLOCK_RATE		2500000
 
-/* For now, all mappings are flat (physical = virtual)
+/* Static peripheral mappings are mapped at the top of the vmalloc region.  The
+ * early uart mapping causes intermediate problems/failure at certain
+ * addresses, including the very top of the vmalloc region.  Map it at an
+ * address that is known to work.
  */
-#define UART0_PHYS			0xE0000000
-#define UART0_VIRT			UART0_PHYS
+#define UART0_PHYS		0xE0000000
+#define UART0_SIZE		SZ_4K
+#define UART0_VIRT		0xF0001000
 
-#define TTC0_PHYS			0xF8001000
-#define TTC0_VIRT			TTC0_PHYS
+#define TTC0_PHYS		0xF8001000
+#define TTC0_SIZE		SZ_4K
+#define TTC0_VIRT		(VMALLOC_END - TTC0_SIZE)
 
-#define SCU_PERIPH_PHYS			0xF8F00000
-#define SCU_PERIPH_VIRT			SCU_PERIPH_PHYS
+#define SCU_PERIPH_PHYS		0xF8F00000
+#define SCU_PERIPH_SIZE		SZ_8K
+#define SCU_PERIPH_VIRT		(TTC0_VIRT - SCU_PERIPH_SIZE)
 
 /* The following are intended for the devices that are mapped early */
 
 #define TTC0_BASE			IOMEM(TTC0_VIRT)
 #define SCU_PERIPH_BASE			IOMEM(SCU_PERIPH_VIRT)
 
-/*
- * Mandatory for CONFIG_LL_DEBUG, UART is mapped virtual = physical
- */
 #define LL_UART_PADDR	UART0_PHYS
 #define LL_UART_VADDR	UART0_VIRT
 
-- 
1.8.0

