KVM: selftests: Add quadword MMIO accessors

The base registers in the GIC ITS and redistributor for LPIs are 64 bits
wide. Add quadword accessors to poke at them.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-16-oliver.upton@linux.devSigned-off-by: Marc Zyngier <maz@kernel.org>

tools/testing/selftests/kvm/include/aarch64/processor.h

@@ -177,11 +177,28 @@ static __always_inline u32 __raw_readl(const volatile void *addr)
 	return val;
 }
 
+static __always_inline void __raw_writeq(u64 val, volatile void *addr)
+{
+	asm volatile("str %0, [%1]" : : "rZ" (val), "r" (addr));
+}
+
+static __always_inline u64 __raw_readq(const volatile void *addr)
+{
+	u64 val;
+	asm volatile("ldr %0, [%1]" : "=r" (val) : "r" (addr));
+	return val;
+}
+
 #define writel_relaxed(v,c)	((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
 #define readl_relaxed(c)	({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
+#define writeq_relaxed(v,c)	((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
+#define readq_relaxed(c)	({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
 
 #define writel(v,c)		({ __iowmb(); writel_relaxed((v),(c));})
 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(__v); __v; })
+#define writeq(v,c)		({ __iowmb(); writeq_relaxed((v),(c));})
+#define readq(c)		({ u64 __v = readq_relaxed(c); __iormb(__v); __v; })
+
 
 static inline void local_irq_enable(void)
 {