These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / arch / arc / include / asm / io.h

diff --git a/kernel/arch/arc/include/asm/io.h b/kernel/arch/arc/include/asm/io.h
index cabd518..694ece8 100644 (file)
--- a/kernel/arch/arc/include/asm/io.h
+++ b/kernel/arch/arc/include/asm/io.h
@@ -20,6 +20,7 @@ extern void iounmap(const void __iomem *addr);
 
 #define ioremap_nocache(phy, sz)       ioremap(phy, sz)
 #define ioremap_wc(phy, sz)            ioremap(phy, sz)
+#define ioremap_wt(phy, sz)            ioremap(phy, sz)
 
 /* Change struct page to physical address */
 #define page_to_phys(page)             (page_to_pfn(page) << PAGE_SHIFT)
@@ -98,9 +99,45 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr)
 
 }
 
-#define readb_relaxed readb
-#define readw_relaxed readw
-#define readl_relaxed readl
+#ifdef CONFIG_ISA_ARCV2
+#include <asm/barrier.h>
+#define __iormb()              rmb()
+#define __iowmb()              wmb()
+#else
+#define __iormb()              do { } while (0)
+#define __iowmb()              do { } while (0)
+#endif
+
+/*
+ * MMIO can also get buffered/optimized in micro-arch, so barriers needed
+ * Based on ARM model for the typical use case
+ *
+ *     <ST [DMA buffer]>
+ *     <writel MMIO "go" reg>
+ *  or:
+ *     <readl MMIO "status" reg>
+ *     <LD [DMA buffer]>
+ *
+ * http://lkml.kernel.org/r/20150622133656.GG1583@arm.com
+ */
+#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 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); })
+
+/*
+ * Relaxed API for drivers which can handle any ordering themselves
+ */
+#define readb_relaxed(c)       __raw_readb(c)
+#define readw_relaxed(c)       __raw_readw(c)
+#define readl_relaxed(c)       __raw_readl(c)
+
+#define writeb_relaxed(v,c)    __raw_writeb(v,c)
+#define writew_relaxed(v,c)    __raw_writew(v,c)
+#define writel_relaxed(v,c)    __raw_writel(v,c)
 
 #include <asm-generic/io.h>