On Tuesday 30 August 2011, Richard Kuo wrote:

Changed read/write to use inline assembly.

Rearranged the file and put all the ioport stuff at the bottom.  For now
I'd like to just leave the stubs in there in case they need to be
filled out later; plus things don't compile.

We still seem to need IO_SPACE_LIMIT to be defined, particularly to something
large, as we have drivers that request resources with IORESOURCE_IO that
are memory mapped IO.  The ioread/iowrites work as they select the correct
routine to use.

Which drivers? If the drivers are buggy, better fix them than working around
in the architecture.

I have experimental patches in the tmp/randconfig3 branch of the arm-soc.git
tree to remove the need for PIO functions in ARM. Please have a look there
if you are interested.

+/*
+ * We don't have PCI yet.
+ */
+#define IO_SPACE_LIMIT 0xffffffff
+#define _IO_BASE 0x0

If you absolutely insist on defining these, at least make them meaningful,
e.g. defining _IO_BASE to an unused location in the virtual address space,
and IO_SPACE_LIMIT small enough to be harmless, at most 0xffff.

If you ever gain PCI support, you can then map the PCI I/O space into that
area.

+static inline void memcpy_fromio(void *dst, const volatile void __iomem *src,
+	int count)
+{
+	memcpy(dst, (void *) src, count);
+}
+
+static inline void memcpy_toio(volatile void __iomem *dst, const void *src,
+	int count)
+{
+	memcpy((void *) dst, src, count);
+}

This will need __force in order to build with sparse.

+#define PCI_IO_ADDR	volatile void __iomem *

Better make _IO_BASE have the right type to start with, like

#define _IO_BASE ((void __iomem *)0xefff0000)
static inline u8 inb(unsigned long port)
{
	return readb(_IO_BASE + (port & IO_SPACE_LIMIT));
}

static inline void outb(u8 data, unsigned long port)
{
	writeb(data, _IO_BASE + (port & IO_SPACE_LIMIT));
}

+/*  _p means "pause until the I/O completes"  */
+#define outb_p outb
+#define outw_p outw
+#define outl_p outl
+
+#define inb_p inb
+#define inw_p inw
+#define inl_p inl

It doesn't actually mean that. It means 'pause for a bit longer'. The inb/outb
family of functions is already required to wait for the I/O to complete,
unlike readb/writeb, which only needs to wait for inbound data, while
outbound writes are posted to the bus without waiting for the data to arrive.

+static inline void insb(unsigned long addr, void *buffer, int count)
+{
+	printk(KERN_INFO "insb not implemented\n");
+}
+
+static inline void insw(unsigned long addr, void *buffer, int count)
+{
+	printk(KERN_INFO "insw not implemented\n");
+}
+
+static inline void insl(unsigned long addr, void *buffer, int count)
+{
+	printk(KERN_INFO "insl not implemented\n");
+}
+
+static inline void outsb(unsigned long addr, const void *buffer, int count)
+{
+	printk(KERN_INFO "outsb not implemented\n");
+}
+
+static inline void outsw(unsigned long addr, const void *buffer, int count)
+{
+	printk(KERN_INFO "outsw not implemented\n");
+}
+
+static inline void outsl(unsigned long addr, const void *buffer, int count)
+{
+	printk(KERN_INFO "outsl not implemented\n");
+}

Either just add the obvious implementations adding _IO_BASE as above
or stub these out to create a link time error in drivers using them.
If a driver relies on these functions, it won't work anyway, so it's
better to not even build it.

+/*  generic versions defined in lib/iomap.c  */
+extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
+extern void ioport_unmap(void __iomem *addr);

You can also just set CONFIG_NO_IOPORT (CONFIG_NO_IOPORT_MAP once my
patches went in) to remove support for ioport_map.

	Arnd