[PATCH] atmel_serial: Pass fixed register mappings through platform_data

In order to initialize the serial console early, the atmel_serial
driver had to do a hack where it compared the physical address of the
port with an address known to be permanently mapped, and used it as a
virtual address. This got around the limitation that ioremap() isn't
always available when the console is being initalized.

This patch removes that hack and replaces it with a new "regs" field
in struct atmel_uart_data that the board-specific code can initialize
to a fixed virtual mapping for platform devices where this is possible.
It also initializes the DBGU's regs field with the address the driver
used to check against.

On AVR32, the "regs" field is initialized from the physical base
address when this it can be accessed through a permanently 1:1 mapped
segment, i.e. the P4 segment.

If regs is NULL, the console initialization is delayed until the "real"
driver is up and running and ioremap() can be used.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/asm-arm/arch-at91rm9200/board.h b/include/asm-arm/arch-at91rm9200/board.h
index d56527055c9d..3cc9aec80f9d 100644
--- a/include/asm-arm/arch-at91rm9200/board.h
+++ b/include/asm-arm/arch-at91rm9200/board.h
@@ -103,6 +103,7 @@ extern void __init at91_init_serial(struct at91_uart_config *config);
 struct atmel_uart_data {
 	short		use_dma_tx;	/* use transmit DMA? */
 	short		use_dma_rx;	/* use receive DMA? */
+	void __iomem	*regs;		/* virtual base address, if any */
 };
 extern void __init at91_add_device_serial(void);