Nyaaori/rockbox
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Make atomic bit modification functions return previous value.

Browse source 
Change-Id: I19a94cf946735e1d9e51c3207cd82198fd4dfc1a
This commit is contained in:
Michael Sevakis 2017-01-24 10:15:53 -05:00
parent 65e7617ab6
commit f728559bf9
3 changed files with 68 additions and 55 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
firmware/export/system.h
View file

@ -163,14 +163,15 @@ static inline __attribute__((always_inline))
uint32_t isolate_first_bit(uint32_t val) uint32_t isolate_first_bit(uint32_t val)
{ return val & -val; } { return val & -val; }
/* Functions to set and clear register or variable bits atomically */ /* Functions to set and clear register or variable bits atomically;
void bitmod16(volatile uint16_t *addr, uint16_t bits, uint16_t mask); * return value is the previous value of *addr */
void bitset16(volatile uint16_t *addr, uint16_t mask); uint16_t bitmod16(volatile uint16_t *addr, uint16_t bits, uint16_t mask);
void bitclr16(volatile uint16_t *addr, uint16_t mask); uint16_t bitset16(volatile uint16_t *addr, uint16_t mask);
uint16_t bitclr16(volatile uint16_t *addr, uint16_t mask);
void bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask); uint32_t bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask);
void bitset32(volatile uint32_t *addr, uint32_t mask); uint32_t bitset32(volatile uint32_t *addr, uint32_t mask);
void bitclr32(volatile uint32_t *addr, uint32_t mask); uint32_t bitclr32(volatile uint32_t *addr, uint32_t mask);
/* gcc 3.4 changed the format of the constraints */ /* gcc 3.4 changed the format of the constraints */
#if (__GNUC__ >= 3) && (__GNUC_MINOR__ > 3) || (__GNUC__ >= 4) #if (__GNUC__ >= 3) && (__GNUC_MINOR__ > 3) || (__GNUC__ >= 4)

78
firmware/target/arm/bits-armv4.S
View file

@ -20,7 +20,7 @@
****************************************************************************/ ****************************************************************************/
/*************************************************************************** /***************************************************************************
* void bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask) * uint32_t bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask)
*/ */
.section .text.bitmod32, "ax", %progbits .section .text.bitmod32, "ax", %progbits
.align 2 .align 2
@ -30,54 +30,59 @@ bitmod32:
mrs r12, cpsr mrs r12, cpsr
orr r3, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r3 msr cpsr_c, r3
ldr r3, [r0] mov r3, r0
ldr r0, [r3]
and r1, r1, r2 @ Only allow mod of bits in 'mask' and r1, r1, r2 @ Only allow mod of bits in 'mask'
bic r3, r3, r2 @ Clear mask bits bic r2, r0, r2 @ Clear mask bits
orr r3, r3, r1 @ Set according to 'bits' orr r1, r2, r1 @ Set according to 'bits'
str r3, [r0] str r1, [r3]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitmod32, .-bitmod32 .size bitmod32, .-bitmod32
/*************************************************************************** /***************************************************************************
* void bitset32(volatile uint32_t *addr, uint32_t mask) * uint32_t bitset32(volatile uint32_t *addr, uint32_t mask)
*/ */
.section .text.bitset32, "ax", %progbits .section .text.bitset32, "ax", %progbits
.align 2 .align 2
.global bitset32 .global bitset32
.type bitset32, %function .type bitset32, %function
bitset32: bitset32:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
orr r2, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r2 msr cpsr_c, r3
ldr r2, [r0] ldr r0, [r2]
orr r2, r2, r1 orr r1, r0, r1
str r2, [r0] str r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitset32, .-bitset32 .size bitset32, .-bitset32
/*************************************************************************** /***************************************************************************
* void bitclr32(volatile uint32_t *addr, uint32_t mask) * uint32_t bitclr32(volatile uint32_t *addr, uint32_t mask)
*/ */
.section .text.bitclr32, "ax", %progbits .section .text.bitclr32, "ax", %progbits
.align 2 .align 2
.global bitclr32 .global bitclr32
.type bitclr32, %function .type bitclr32, %function
bitclr32: bitclr32:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
orr r2, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r2 msr cpsr_c, r3
ldr r2, [r0] ldr r0, [r2]
bic r2, r2, r1 bic r1, r0, r1
str r2, [r0] str r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitclr32, .-bitclr32 .size bitclr32, .-bitclr32
/*************************************************************************** /***************************************************************************
* void bitmod16(volatile uint16_t *addr, uint16_t bits, uint16_t mask) * uint16_t bitmod16(volatile uint16_t *addr, uint16_t bits, uint16_t mask)
*/ */
.section .text.bitmod16, "ax", %progbits .section .text.bitmod16, "ax", %progbits
.align 2 .align 2
@ -87,49 +92,52 @@ bitmod16:
mrs r12, cpsr mrs r12, cpsr
orr r3, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r3 msr cpsr_c, r3
ldrh r3, [r0] mov r3, r0
ldrh r0, [r3]
and r1, r1, r2 @ Only allow mod of bits in 'mask' and r1, r1, r2 @ Only allow mod of bits in 'mask'
bic r3, r3, r2 @ Clear mask bits bic r2, r0, r2 @ Clear mask bits
orr r3, r3, r1 @ Set according to 'bits' orr r1, r2, r1 @ Set according to 'bits'
strh r3, [r0] strh r1, [r3]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitmod16, .-bitmod16 .size bitmod16, .-bitmod16
/*************************************************************************** /***************************************************************************
* void bitset16(volatile uint16_t *addr, uint16_t mask) * uint16_t bitset16(volatile uint16_t *addr, uint16_t mask)
*/ */
.section .text.bitset16, "ax", %progbits .section .text.bitset16, "ax", %progbits
.align 2 .align 2
.global bitset16 .global bitset16
.type bitset16, %function .type bitset16, %function
bitset16: bitset16:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
orr r2, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r2 msr cpsr_c, r3
ldrh r2, [r0] ldrh r0, [r2]
orr r2, r2, r1 orr r1, r0, r1
strh r2, [r0] strh r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitset16, .-bitset16 .size bitset16, .-bitset16
/*************************************************************************** /***************************************************************************
* void bitclr16(volatile uint16_t *addr, uint16_t mask) * uint16_t bitclr16(volatile uint16_t *addr, uint16_t mask)
*/ */
.section .text.bitclr16, "ax", %progbits .section .text.bitclr16, "ax", %progbits
.align 2 .align 2
.global bitclr16 .global bitclr16
.type bitclr16, %function .type bitclr16, %function
bitclr16: bitclr16:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
orr r2, r12, #0xc0 orr r3, r12, #0xc0
msr cpsr_c, r2 msr cpsr_c, r3
ldrh r2, [r0] ldrh r0, [r2]
bic r2, r2, r1 bic r1, r0, r1
strh r2, [r0] strh r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitclr16, .-bitclr16 .size bitclr16, .-bitclr16

30
firmware/target/arm/bits-armv6.S
View file

@ -20,55 +20,59 @@
****************************************************************************/ ****************************************************************************/
/*************************************************************************** /***************************************************************************
* void bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask) * uint32_t bitmod32(volatile uint32_t *addr, uint32_t bits, uint32_t mask)
*/ */
.section .text.bitmod32, "ax", %progbits .section .text.bitmod32, "ax", %progbits
.align 2 .align 2
.global bitmod32 .global bitmod32
.type bitmod32, %function .type bitmod32, %function
bitmod32: bitmod32:
mov r3, r0
mrs r12, cpsr mrs r12, cpsr
cpsid if cpsid if
ldr r3, [r0] ldr r0, [r3]
and r1, r1, r2 @ Only allow mod of bits in 'mask' and r1, r1, r2 @ Only allow mod of bits in 'mask'
bic r3, r3, r2 @ Clear mask bits bic r2, r0, r2 @ Clear mask bits
orr r3, r3, r1 @ Set according to 'bits' orr r1, r2, r1 @ Set according to 'bits'
str r3, [r0] str r1, [r3]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitmod32, .-bitmod32 .size bitmod32, .-bitmod32
/*************************************************************************** /***************************************************************************
* void bitset32(volatile uint32_t *addr, uint32_t mask) * uint32_t bitset32(volatile uint32_t *addr, uint32_t mask)
*/ */
.section .text.bitset32, "ax", %progbits .section .text.bitset32, "ax", %progbits
.align 2 .align 2
.global bitset32 .global bitset32
.type bitset32, %function .type bitset32, %function
bitset32: bitset32:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
cpsid if cpsid if
ldr r2, [r0] ldr r0, [r2]
orr r2, r2, r1 orr r1, r0, r1
str r2, [r0] str r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitset32, .-bitset32 .size bitset32, .-bitset32
/*************************************************************************** /***************************************************************************
* void bitclr32(volatile uint32_t *addr, uint32_t mask) * uint32_t bitclr32(volatile uint32_t *addr, uint32_t mask)
*/ */
.section .text.bitclr32, "ax", %progbits .section .text.bitclr32, "ax", %progbits
.align 2 .align 2
.global bitclr32 .global bitclr32
.type bitclr32, %function .type bitclr32, %function
bitclr32: bitclr32:
mov r2, r0
mrs r12, cpsr mrs r12, cpsr
cpsid if cpsid if
ldr r2, [r0] ldr r0, [r2]
bic r2, r2, r1 bic r1, r0, r1
str r2, [r0] str r1, [r2]
msr cpsr_c, r12 msr cpsr_c, r12
bx lr bx lr
.size bitclr32, .-bitclr32 .size bitclr32, .-bitclr32