Mostly complete rewrite of the FRV atomic implementation, instead of
using assembly files, use inline assembler.

The out-of-line CONFIG option makes a bit of a mess of things, but a
little CPP trickery gets that done too.

FRV already had the atomic logic ops but under a non standard name,
the reimplementation provides the generic names and provides the
intermediate form required for the bitops implementation.

The slightly inconsistent __atomic32_fetch_##op naming is because
__atomic_fetch_##op conlicts with GCC builtin functions.

The 64bit atomic ops use the inline assembly %Ln construct to access
the low word register (r+1), afaik this construct was not previously
used in the kernel and is completely undocumented, but I found it in
the FRV GCC code and it seems to work.

FRV had a non-standard definition of atomic_{clear,set}_mask() which
would work types other than atomic_t, the one user relying on that
(arch/frv/kernel/dma.c) got converted to use the new intermediate
form.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Implement atomic64_t and its ops for FRV.  Tested with the following patch:

	diff --git a/arch/frv/kernel/setup.c b/arch/frv/kernel/setup.c
	index 55e4fab..086d50d 100644
	--- a/arch/frv/kernel/setup.c
	+++ b/arch/frv/kernel/setup.c
	@@ -746,6 +746,52 @@ static void __init parse_cmdline_early(char *cmdline)

	 } /* end parse_cmdline_early() */

	+static atomic64_t xxx;
	+
	+static void test_atomic64(void)
	+{
	+	atomic64_set(&xxx, 0x12300000023LL);
	+
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0x12300000023LL);
	+	mb();
	+	if (atomic64_inc_return(&xxx) != 0x12300000024LL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0x12300000024LL);
	+	mb();
	+	if (atomic64_sub_return(0x36900000050LL, &xxx) != -0x2460000002cLL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != -0x2460000002cLL);
	+	mb();
	+	if (atomic64_dec_return(&xxx) != -0x2460000002dLL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != -0x2460000002dLL);
	+	mb();
	+	if (atomic64_add_return(0x36800000001LL, &xxx) != 0x121ffffffd4LL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0x121ffffffd4LL);
	+	mb();
	+	if (atomic64_cmpxchg(&xxx, 0x123456789abcdefLL, 0x121ffffffd4LL) != 0x121ffffffd4LL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0x121ffffffd4LL);
	+	mb();
	+	if (atomic64_cmpxchg(&xxx, 0x121ffffffd4LL, 0x123456789abcdefLL) != 0x121ffffffd4LL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0x123456789abcdefLL);
	+	mb();
	+	if (atomic64_xchg(&xxx, 0xabcdef123456789LL) != 0x123456789abcdefLL)
	+		BUG();
	+	mb();
	+	BUG_ON(atomic64_read(&xxx) != 0xabcdef123456789LL);
	+	mb();
	+}
	+
	 /*****************************************************************************/
	 /*
	  *
	@@ -845,6 +891,8 @@ void __init setup_arch(char **cmdline_p)
	 //	asm volatile("movgs %0,timerd" :: "r"(10000000));
	 //	__set_HSR(0, __get_HSR(0) | HSR0_ETMD);

	+	test_atomic64();
	+
	 } /* end setup_arch() */

	 #if 0

Note that this doesn't cover all the trivial wrappers, but does cover all the
substantial implementations.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>