core/minute-ia: add Zephyr compatible atomic functions

Add atomic functions with prototypes equal to the ones in Zephyr.

It is done as a part of porting to Zephyr, the next step is to use in
the code atomic_* instead of deprecated_atomic_*.

Some atomic functions in Zephyr return a value e.g. atomic_add - it
returns the value of the variable before the add operation.
The current state of ATOMIC_OP macro is not designed to return such value
so instead of reworking it or writing new custom asm code just use
builtin functions.

The __atomic_* builtins support variables with different sizes so use
them in *_u8 functions as well.
For "and" operation, it compiles to "andb" for u8 and to "andl" for u32.

BUG=b:169151160
BRANCH=none
TEST=buildall

Signed-off-by: Dawid Niedzwiecki <dn@semihalf.com>
Change-Id: I498ca3dbb14aea6afc2f7a525c530eede7f31fe2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2448497
Reviewed-by: Jett Rink <jettrink@chromium.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/core/minute-ia/atomic.h b/core/minute-ia/atomic.h
index 598fc5b3ed..f55018d445 100644
--- a/core/minute-ia/atomic.h
+++ b/core/minute-ia/atomic.h
@@ -11,6 +11,9 @@
 #include "common.h"
 #include "util.h"
 
+typedef int atomic_t;
+typedef atomic_t atomic_val_t;
+
 #define ATOMIC_OP(asm_op, a, v) do {		\
 	__asm__ __volatile__ (			\
 		ASM_LOCK_PREFIX #asm_op " %1, %0\n"	\
@@ -43,40 +46,75 @@ static inline void deprecated_atomic_or_u8(uint8_t *addr, uint8_t bits)
 	ATOMIC_OP(or, addr, bits);
 }
 
+static inline atomic_val_t atomic_or_u8(uint8_t *addr, uint8_t bits)
+{
+	return __atomic_fetch_or(addr, bits, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_and_u8(uint8_t *addr, uint8_t bits)
 {
 	ATOMIC_OP(and, addr, bits);
 }
 
+static inline atomic_val_t atomic_and_u8(uint8_t *addr, uint8_t bits)
+{
+	return __atomic_fetch_and(addr, bits, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_clear_bits(uint32_t volatile *addr,
 						uint32_t bits)
 {
 	ATOMIC_OP(andl, addr, ~bits);
 }
 
+static inline void atomic_clear_bits(atomic_t *addr, atomic_val_t bits)
+{
+	__atomic_fetch_and(addr, ~bits, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_or(uint32_t volatile *addr, uint32_t bits)
 {
 	ATOMIC_OP(orl, addr, bits);
 }
 
+static inline atomic_val_t atomic_or(atomic_t *addr, atomic_val_t bits)
+{
+	return __atomic_fetch_or(addr, bits, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_add(uint32_t volatile *addr,
 					 uint32_t value)
 {
 	ATOMIC_OP(addl, addr, value);
 }
 
+static inline atomic_val_t atomic_add(atomic_t *addr, atomic_val_t value)
+{
+	return __atomic_fetch_add(addr, value, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_and(uint32_t volatile *addr,
 					 uint32_t value)
 {
 	ATOMIC_OP(andl, addr, value);
 }
 
+static inline atomic_val_t atomic_and(atomic_t *addr, atomic_val_t bits)
+{
+	return __atomic_fetch_and(addr, bits, __ATOMIC_SEQ_CST);
+}
+
 static inline void deprecated_atomic_sub(uint32_t volatile *addr,
 					 uint32_t value)
 {
 	ATOMIC_OP(subl, addr, value);
 }
 
+static inline atomic_val_t atomic_sub(atomic_t *addr, atomic_val_t value)
+{
+	return __atomic_fetch_sub(addr, value, __ATOMIC_SEQ_CST);
+}
+
 static inline uint32_t deprecated_atomic_read_clear(uint32_t volatile *addr)
 {
 	int ret = 0;
@@ -91,4 +129,9 @@ static inline uint32_t deprecated_atomic_read_clear(uint32_t volatile *addr)
 	return ret;
 }
 
+static inline atomic_val_t atomic_read_clear(atomic_t *addr)
+{
+	return __atomic_exchange_n(addr, 0, __ATOMIC_SEQ_CST);
+}
+
 #endif  /* __CROS_EC_ATOMIC_H */