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authorNicolas Pitre <nicolas.pitre@linaro.org>2011-09-01 00:48:04 -0400
committerNicolas Pitre <nico@fluxnic.net>2011-09-26 10:11:27 -0400
commitfa808a1ba5f9d40ad47c31f63691b1ded03a46f8 (patch)
tree1ccd2315bba082cf4fa9a831bcad683b197cc01c /arch
parent28362d5153757dcb7af9a63978202c1ed1e3cf39 (diff)
downloadlinux-fa808a1ba5f9d40ad47c31f63691b1ded03a46f8.tar.bz2
ARM: mach-omap2: clean up debug-macro.S
This achieves two goals: 1) Get rid of omap_uart_v2p() and omap_uart_p2v() which were the last users of PLAT_PHYS_OFFSET. 2) Remove the probing of the M bit in the CP15 control reg and make the access to the .data variables completely position independent. There is a catch though: the busyuart macro needs to know where the LSR register is which might be at a different offset depending on the hardware. Given that this macro is given only two registers and that one of them must be preserved, the trick is to always pass the LSR register address around, and deduce the base address for the THR register by masking out the LSR offset in senduart instead. Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Kevin Hilman <khilman@ti.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mach-omap2/include/mach/debug-macro.S70
1 files changed, 31 insertions, 39 deletions
diff --git a/arch/arm/mach-omap2/include/mach/debug-macro.S b/arch/arm/mach-omap2/include/mach/debug-macro.S
index 745e2ff3e906..13f98e59cfef 100644
--- a/arch/arm/mach-omap2/include/mach/debug-macro.S
+++ b/arch/arm/mach-omap2/include/mach/debug-macro.S
@@ -13,15 +13,10 @@
#include <linux/serial_reg.h>
-#include <asm/memory.h>
-
#include <plat/serial.h>
#define UART_OFFSET(addr) ((addr) & 0x00ffffff)
-#define omap_uart_v2p(x) ((x) - PAGE_OFFSET + PLAT_PHYS_OFFSET)
-#define omap_uart_p2v(x) ((x) - PLAT_PHYS_OFFSET + PAGE_OFFSET)
-
.pushsection .data
omap_uart_phys: .word 0
omap_uart_virt: .word 0
@@ -37,16 +32,16 @@ omap_uart_lsr: .word 0
.macro addruart, rp, rv, tmp
/* Use omap_uart_phys/virt if already configured */
-10: mrc p15, 0, \rp, c1, c0
- tst \rp, #1 @ MMU enabled?
- ldreq \rp, =omap_uart_v2p(omap_uart_phys) @ MMU disabled
- ldrne \rp, =omap_uart_phys @ MMU enabled
- add \rv, \rp, #4 @ omap_uart_virt
- ldr \rp, [\rp, #0]
- ldr \rv, [\rv, #0]
+10: adr \rp, 99f @ get effective addr of 99f
+ ldr \rv, [\rp] @ get absolute addr of 99f
+ sub \rv, \rv, \rp @ offset between the two
+ ldr \rp, [\rp, #4] @ abs addr of omap_uart_phys
+ sub \tmp, \rp, \rv @ make it effective
+ ldr \rp, [\tmp, #0] @ omap_uart_phys
+ ldr \rv, [\tmp, #4] @ omap_uart_virt
cmp \rp, #0 @ is port configured?
cmpne \rv, #0
- bne 99f @ already configured
+ bne 100f @ already configured
/* Check the debug UART configuration set in uncompress.h */
mov \rp, pc
@@ -105,50 +100,47 @@ omap_uart_lsr: .word 0
b 98f
83: mov \rp, #UART_OFFSET(TI816X_UART3_BASE)
b 98f
+
95: ldr \rp, =ZOOM_UART_BASE
- mrc p15, 0, \rv, c1, c0
- tst \rv, #1 @ MMU enabled?
- ldreq \rv, =omap_uart_v2p(omap_uart_phys) @ MMU disabled
- ldrne \rv, =omap_uart_phys @ MMU enabled
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #0] @ omap_uart_phys
ldr \rp, =ZOOM_UART_VIRT
- add \rv, \rv, #4 @ omap_uart_virt
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #4] @ omap_uart_virt
mov \rp, #(UART_LSR << ZOOM_PORT_SHIFT)
- add \rv, \rv, #4 @ omap_uart_lsr
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #8] @ omap_uart_lsr
b 10b
/* Store both phys and virt address for the uart */
98: add \rp, \rp, #0x48000000 @ phys base
- mrc p15, 0, \rv, c1, c0
- tst \rv, #1 @ MMU enabled?
- ldreq \rv, =omap_uart_v2p(omap_uart_phys) @ MMU disabled
- ldrne \rv, =omap_uart_phys @ MMU enabled
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #0] @ omap_uart_phys
sub \rp, \rp, #0x48000000 @ phys base
add \rp, \rp, #0xfa000000 @ virt base
- add \rv, \rv, #4 @ omap_uart_virt
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #4] @ omap_uart_virt
mov \rp, #(UART_LSR << OMAP_PORT_SHIFT)
- add \rv, \rv, #4 @ omap_uart_lsr
- str \rp, [\rv, #0]
+ str \rp, [\tmp, #8] @ omap_uart_lsr
b 10b
-99:
+
+ .align
+99: .word .
+ .word omap_uart_phys
+ .ltorg
+
+100: /* Pass the UART_LSR reg address */
+ ldr \tmp, [\tmp, #8] @ omap_uart_lsr
+ add \rp, \rp, \tmp
+ add \rv, \rv, \tmp
.endm
.macro senduart,rd,rx
- strb \rd, [\rx]
+ orr \rd, \rd, \rx, lsl #24 @ preserve LSR reg offset
+ bic \rx, \rx, #0xff @ get base (THR) reg address
+ strb \rd, [\rx] @ send lower byte of rd
+ orr \rx, \rx, \rd, lsr #24 @ restore original rx (LSR)
+ bic \rd, \rd, #(0xff << 24) @ restore original rd
.endm
.macro busyuart,rd,rx
-1001: mrc p15, 0, \rd, c1, c0
- tst \rd, #1 @ MMU enabled?
- ldreq \rd, =omap_uart_v2p(omap_uart_lsr) @ MMU disabled
- ldrne \rd, =omap_uart_lsr @ MMU enabled
- ldr \rd, [\rd, #0]
- ldrb \rd, [\rx, \rd]
+1001: ldrb \rd, [\rx] @ rx contains UART_LSR address
and \rd, \rd, #(UART_LSR_TEMT | UART_LSR_THRE)
teq \rd, #(UART_LSR_TEMT | UART_LSR_THRE)
bne 1001b