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ns16550: change map_sysmem to map_physmem 

Change map_sysmem() to map_physmem(,,MAP_NOCACHE). Though map_sysmem()
can be used to map system memory, it might be wrong to use it for I/O
ports.  The map_physmem() serves the same purpose to translate physical
address to virtual address with the additional flag to take care of cache
property. Most drivers use map_physmem() since I/O ports access should be
uncached. As ns16550 is a driver, it should use map_physmem() rather
than map_sysmem().

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Thomas Chou 2015-11-19 21:48:04 +08:00 committed by Tom Rini
parent b1e361b605
commit 77d7b5cd40
1 changed files with 2 additions and 3 deletions
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5
drivers/serial/ns16550.c
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@ -8,7 +8,6 @@
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <mapmem.h>
#include <ns16550.h>
#include <serial.h>
#include <watchdog.h>
@ -97,7 +96,7 @@ static void ns16550_writeb(NS16550_t port, int offset, int value)
unsigned char *addr;
offset *= 1 << plat->reg_shift;
addr = map_sysmem(plat->base, 0) + offset;
addr = map_physmem(plat->base, 0, MAP_NOCACHE) + offset;
/*
* As far as we know it doesn't make sense to support selection of
* these options at run-time, so use the existing CONFIG options.
@ -111,7 +110,7 @@ static int ns16550_readb(NS16550_t port, int offset)
unsigned char *addr;
offset *= 1 << plat->reg_shift;
addr = map_sysmem(plat->base, 0) + offset;
addr = map_physmem(plat->base, 0, MAP_NOCACHE) + offset;
return serial_in_shift(addr, plat->reg_shift);
}