linux/arch/arm/mach-imx/ssi-fiq.S
Russell King 8478132a87 Revert "arm: move exports to definitions"
This reverts commit 4dd1837d75.

Moving the exports for assembly code into the assembly files breaks
KSYM trimming, but also breaks modversions.

While fixing the KSYM trimming is trivial, fixing modversions brings
us to a technically worse position that we had prior to the above
change:

- We end up with the prototype definitions divorsed from everything
  else, which means that adding or removing assembly level ksyms
  become more fragile:
  * if adding a new assembly ksyms export, a missed prototype in
    asm-prototypes.h results in a successful build if no module in
    the selected configuration makes use of the symbol.
  * when removing a ksyms export, asm-prototypes.h will get forgotten,
    with armksyms.c, you'll get a build error if you forget to touch
    the file.

- We end up with the same amount of include files and prototypes,
  they're just in a header file instead of a .c file with their
  exports.

As for lines of code, we don't get much of a size reduction:
 (original commit)
 47 files changed, 131 insertions(+), 208 deletions(-)
 (fix for ksyms trimming)
 7 files changed, 18 insertions(+), 5 deletions(-)
 (two fixes for modversions)
 1 file changed, 34 insertions(+)
 3 files changed, 7 insertions(+), 2 deletions(-)
which results in a net total of only 25 lines deleted.

As there does not seem to be much benefit from this change of approach,
revert the change.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-11-23 10:00:03 +00:00

148 lines
2.9 KiB
ArmAsm

/*
* Copyright (C) 2009 Sascha Hauer <s.hauer@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* r8 = bit 0-15: tx offset, bit 16-31: tx buffer size
* r9 = bit 0-15: rx offset, bit 16-31: rx buffer size
*/
#define SSI_STX0 0x00
#define SSI_SRX0 0x08
#define SSI_SISR 0x14
#define SSI_SIER 0x18
#define SSI_SACNT 0x38
#define SSI_SACNT_AC97EN (1 << 0)
#define SSI_SIER_TFE0_EN (1 << 0)
#define SSI_SISR_TFE0 (1 << 0)
#define SSI_SISR_RFF0 (1 << 2)
#define SSI_SIER_RFF0_EN (1 << 2)
.text
.global imx_ssi_fiq_start
.global imx_ssi_fiq_end
.global imx_ssi_fiq_base
.global imx_ssi_fiq_rx_buffer
.global imx_ssi_fiq_tx_buffer
/*
* imx_ssi_fiq_start is _intentionally_ not marked as a function symbol
* using ENDPROC(). imx_ssi_fiq_start and imx_ssi_fiq_end are used to
* mark the function body so that it can be copied to the FIQ vector in
* the vectors page. imx_ssi_fiq_start should only be called as the result
* of an FIQ: calling it directly will not work.
*/
imx_ssi_fiq_start:
ldr r12, .L_imx_ssi_fiq_base
/* TX */
ldr r13, .L_imx_ssi_fiq_tx_buffer
/* shall we send? */
ldr r11, [r12, #SSI_SIER]
tst r11, #SSI_SIER_TFE0_EN
beq 1f
/* TX FIFO empty? */
ldr r11, [r12, #SSI_SISR]
tst r11, #SSI_SISR_TFE0
beq 1f
mov r10, #0x10000
sub r10, #1
and r10, r10, r8 /* r10: current buffer offset */
add r13, r13, r10
ldrh r11, [r13]
strh r11, [r12, #SSI_STX0]
ldrh r11, [r13, #2]
strh r11, [r12, #SSI_STX0]
ldrh r11, [r13, #4]
strh r11, [r12, #SSI_STX0]
ldrh r11, [r13, #6]
strh r11, [r12, #SSI_STX0]
add r10, #8
lsr r11, r8, #16 /* r11: buffer size */
cmp r10, r11
lslgt r8, r11, #16
addle r8, #8
1:
/* RX */
/* shall we receive? */
ldr r11, [r12, #SSI_SIER]
tst r11, #SSI_SIER_RFF0_EN
beq 1f
/* RX FIFO full? */
ldr r11, [r12, #SSI_SISR]
tst r11, #SSI_SISR_RFF0
beq 1f
ldr r13, .L_imx_ssi_fiq_rx_buffer
mov r10, #0x10000
sub r10, #1
and r10, r10, r9 /* r10: current buffer offset */
add r13, r13, r10
ldr r11, [r12, #SSI_SACNT]
tst r11, #SSI_SACNT_AC97EN
ldr r11, [r12, #SSI_SRX0]
strh r11, [r13]
ldr r11, [r12, #SSI_SRX0]
strh r11, [r13, #2]
/* dummy read to skip slot 12 */
ldrne r11, [r12, #SSI_SRX0]
ldr r11, [r12, #SSI_SRX0]
strh r11, [r13, #4]
ldr r11, [r12, #SSI_SRX0]
strh r11, [r13, #6]
/* dummy read to skip slot 12 */
ldrne r11, [r12, #SSI_SRX0]
add r10, #8
lsr r11, r9, #16 /* r11: buffer size */
cmp r10, r11
lslgt r9, r11, #16
addle r9, #8
1:
@ return from FIQ
subs pc, lr, #4
.align
.L_imx_ssi_fiq_base:
imx_ssi_fiq_base:
.word 0x0
.L_imx_ssi_fiq_rx_buffer:
imx_ssi_fiq_rx_buffer:
.word 0x0
.L_imx_ssi_fiq_tx_buffer:
imx_ssi_fiq_tx_buffer:
.word 0x0
.L_imx_ssi_fiq_end:
imx_ssi_fiq_end: