Defined readq_relaxed()/writeq_relaxed() to read and write 64 bit regs.
This uses ldrd/strd instructions.

Signed-off-by: Ayan Kumar Halder <ayank...@amd.com>
---

Changes from :-
v1 - 1. Use ldrd/strd for readq_relaxed()/writeq_relaxed().
2. No need to use le64_to_cpu() as the returned byte order is already in cpu
endianess.

 xen/arch/arm/include/asm/arm32/io.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/xen/arch/arm/include/asm/arm32/io.h 
b/xen/arch/arm/include/asm/arm32/io.h
index 73a879e9fb..d9d19ad764 100644
--- a/xen/arch/arm/include/asm/arm32/io.h
+++ b/xen/arch/arm/include/asm/arm32/io.h
@@ -72,6 +72,22 @@ static inline u32 __raw_readl(const volatile void __iomem 
*addr)
         return val;
 }
 
+static inline u64 __raw_readq(const volatile void __iomem *addr)
+{
+        u64 val;
+        asm volatile("ldrd %Q1, %R1, %0"
+                     : "+Qo" (*(volatile u64 __force *)addr),
+                       "=r" (val));
+        return val;
+}
+
+static inline void __raw_writeq(u64 val, const volatile void __iomem *addr)
+{
+    asm volatile("strd %Q1, %R1, %0"
+                 : "+Q" (*(volatile u64 __force *)addr)
+                 : "r" (val));
+}
+
 #define __iormb()               rmb()
 #define __iowmb()               wmb()
 
@@ -80,17 +96,22 @@ static inline u32 __raw_readl(const volatile void __iomem 
*addr)
                                         __raw_readw(c)); __r; })
 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
                                         __raw_readl(c)); __r; })
+#define readq_relaxed(c) ({ u64 __r = le64_to_cpu((__force __le64) \
+                                        __raw_readq(c)); __r; })
 
 #define writeb_relaxed(v,c)     __raw_writeb(v,c)
 #define writew_relaxed(v,c)     __raw_writew((__force u16) cpu_to_le16(v),c)
 #define writel_relaxed(v,c)     __raw_writel((__force u32) cpu_to_le32(v),c)
+#define writeq_relaxed(v,c)     __raw_writeq((__force u64) cpu_to_le64(v),c)
 
 #define readb(c)                ({ u8  __v = readb_relaxed(c); __iormb(); __v; 
})
 #define readw(c)                ({ u16 __v = readw_relaxed(c); __iormb(); __v; 
})
 #define readl(c)                ({ u32 __v = readl_relaxed(c); __iormb(); __v; 
})
+#define readq(c)                ({ u64 __v = readq_relaxed(c); __iormb(); __v; 
})
 
 #define writeb(v,c)             ({ __iowmb(); writeb_relaxed(v,c); })
 #define writew(v,c)             ({ __iowmb(); writew_relaxed(v,c); })
 #define writel(v,c)             ({ __iowmb(); writel_relaxed(v,c); })
+#define writeq(v,c)             ({ __iowmb(); writeq_relaxed(v,c); })
 
 #endif /* _ARM_ARM32_IO_H */
-- 
2.17.1


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