We already emulate 64KiB of port space by directing (in|out)[bwl] accesses
to the __pci_iobase static array.
By have (read|write)[bwlq] access the first 4K of that port space when
trying to access the NULL page.
That way generic drivers like e.g. pinctrl-single can be trivially
described in the device tree without having to worry about runtime fixup
of the base address in the DT.
Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
arch/sandbox/include/asm/io.h | 70 +++++++++++++++++++++++++++++++++++
1 file changed, 70 insertions(+)
diff --git a/arch/sandbox/include/asm/io.h b/arch/sandbox/include/asm/io.h
index eec279b88834..81e9a78151c1 100644
--- a/arch/sandbox/include/asm/io.h
+++ b/arch/sandbox/include/asm/io.h
@@ -3,12 +3,82 @@
#ifndef __ASM_SANDBOX_IO_H
#define __ASM_SANDBOX_IO_H
+#include <linux/types.h>
+#include <linux/compiler.h>
+
#define IO_SPACE_LIMIT 0xffff
/* pacify static analyzers */
#define PCI_IOBASE ((void __iomem *)__pci_iobase)
extern unsigned char __pci_iobase[IO_SPACE_LIMIT];
+/*
+ * Alias first page of I/O memory to I/O port space
+ */
+static inline volatile void __iomem *
+__xlate_addr(const volatile void __iomem *addr)
+{
+ if ((uintptr_t)addr < 0x1000)
+ addr += (uintptr_t)__pci_iobase;
+ return (volatile void __iomem *)addr;
+}
+
+#define __raw_readb __raw_readb
+static inline u8 __raw_readb(const volatile void __iomem *addr)
+{
+ return *(const volatile u8 __force *)__xlate_addr(addr);
+}
+
+#define __raw_readw __raw_readw
+static inline u16 __raw_readw(const volatile void __iomem *addr)
+{
+ return *(const volatile u16 __force *)__xlate_addr(addr);
+}
+
+#define __raw_readl __raw_readl
+static inline u32 __raw_readl(const volatile void __iomem *addr)
+{
+ return *(const volatile u32 __force *)__xlate_addr(addr);
+}
+
+#ifdef CONFIG_64BIT
+#define __raw_readq __raw_readq
+static inline u64 __raw_readq(const volatile void __iomem *addr)
+{
+ return *(const volatile u64 __force *)__xlate_addr(addr);
+}
+#endif /* CONFIG_64BIT */
+
+#define __raw_writeb __raw_writeb
+static inline void __raw_writeb(u8 value, volatile void __iomem *addr)
+{
+ *(volatile u8 __force *)__xlate_addr(addr) = value;
+}
+
+#define __raw_writew __raw_writew
+static inline void __raw_writew(u16 value, volatile void __iomem *addr)
+{
+ *(volatile u16 __force *)__xlate_addr(addr) = value;
+}
+
+#ifndef __raw_writel
+#define __raw_writel __raw_writel
+static inline void __raw_writel(u32 value, volatile void __iomem *addr)
+{
+ *(volatile u32 __force *)__xlate_addr(addr) = value;
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#define __raw_writeq __raw_writeq
+static inline void __raw_writeq(u64 value, volatile void __iomem *addr)
+{
+ *(volatile u64 __force *)__xlate_addr(addr) = value;
+}
+#endif /* CONFIG_64BIT */
+
+#undef __xlate_addr
+
#include <asm-generic/io.h>
#endif /* __ASM_SANDBOX_IO_H */
--
2.39.2
