sh: GUSA atomic rollback support.
This implements kernel-level atomic rollback built on top of gUSA,
as an alternative non-IRQ based atomicity method. This is generally
a faster method for platforms that are lacking the LL/SC pairs that
SH-4A and later use, and is only supportable on legacy cores.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/bitops-grb.h b/include/asm-sh/bitops-grb.h
new file mode 100644
index 0000000..a5907b9
--- /dev/null
+++ b/include/asm-sh/bitops-grb.h
@@ -0,0 +1,169 @@
+#ifndef __ASM_SH_BITOPS_GRB_H
+#define __ASM_SH_BITOPS_GRB_H
+
+static inline void set_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-6, r15 \n\t" /* LOGIN: r15 = size */
+ " mov.l @%1, %0 \n\t" /* load old value */
+ " or %2, %0 \n\t" /* or */
+ " mov.l %0, @%1 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "+r" (a)
+ : "r" (mask)
+ : "memory" , "r0", "r1");
+}
+
+static inline void clear_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = ~(1 << (nr & 0x1f));
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-6, r15 \n\t" /* LOGIN: r15 = size */
+ " mov.l @%1, %0 \n\t" /* load old value */
+ " and %2, %0 \n\t" /* and */
+ " mov.l %0, @%1 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "+r" (a)
+ : "r" (mask)
+ : "memory" , "r0", "r1");
+}
+
+static inline void change_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-6, r15 \n\t" /* LOGIN: r15 = size */
+ " mov.l @%1, %0 \n\t" /* load old value */
+ " xor %2, %0 \n\t" /* xor */
+ " mov.l %0, @%1 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "+r" (a)
+ : "r" (mask)
+ : "memory" , "r0", "r1");
+}
+
+static inline int test_and_set_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-14, r15 \n\t" /* LOGIN: r15 = size */
+ " mov.l @%2, %0 \n\t" /* load old value */
+ " mov %0, %1 \n\t"
+ " tst %1, %3 \n\t" /* T = ((*a & mask) == 0) */
+ " mov #-1, %1 \n\t" /* retvat = -1 */
+ " negc %1, %1 \n\t" /* retval = (mask & *a) != 0 */
+ " or %3, %0 \n\t"
+ " mov.l %0, @%2 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "=&r" (retval),
+ "+r" (a)
+ : "r" (mask)
+ : "memory" , "r0", "r1" ,"t");
+
+ return retval;
+}
+
+static inline int test_and_clear_bit(int nr, volatile void * addr)
+{
+ int mask, retval,not_mask;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+
+ not_mask = ~mask;
+
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-14, r15 \n\t" /* LOGIN */
+ " mov.l @%2, %0 \n\t" /* load old value */
+ " mov %0, %1 \n\t" /* %1 = *a */
+ " tst %1, %3 \n\t" /* T = ((*a & mask) == 0) */
+ " mov #-1, %1 \n\t" /* retvat = -1 */
+ " negc %1, %1 \n\t" /* retval = (mask & *a) != 0 */
+ " and %4, %0 \n\t"
+ " mov.l %0, @%2 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "=&r" (retval),
+ "+r" (a)
+ : "r" (mask),
+ "r" (not_mask)
+ : "memory" , "r0", "r1", "t");
+
+ return retval;
+}
+
+static inline int test_and_change_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile unsigned int *a = addr;
+ unsigned long tmp;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+
+ __asm__ __volatile__ (
+ " .align 2 \n\t"
+ " mova 1f, r0 \n\t" /* r0 = end point */
+ " mov r15, r1 \n\t" /* r1 = saved sp */
+ " mov #-14, r15 \n\t" /* LOGIN */
+ " mov.l @%2, %0 \n\t" /* load old value */
+ " mov %0, %1 \n\t" /* %1 = *a */
+ " tst %1, %3 \n\t" /* T = ((*a & mask) == 0) */
+ " mov #-1, %1 \n\t" /* retvat = -1 */
+ " negc %1, %1 \n\t" /* retval = (mask & *a) != 0 */
+ " xor %3, %0 \n\t"
+ " mov.l %0, @%2 \n\t" /* store new value */
+ "1: mov r1, r15 \n\t" /* LOGOUT */
+ : "=&r" (tmp),
+ "=&r" (retval),
+ "+r" (a)
+ : "r" (mask)
+ : "memory" , "r0", "r1", "t");
+
+ return retval;
+}
+#endif /* __ASM_SH_BITOPS_GRB_H */