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| author | Xenia Ragiadakou <burzalodowa@gmail.com> | 2013-11-15 05:34:08 +0200 |
|---|---|---|
| committer | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2013-12-02 12:59:49 -0800 |
| commit | e8b373326d8efcaf9ec1da8b618556c89bd5ffc4 (patch) | |
| tree | f1c72d9427799f7dfcacbb7fe77ac35b60154c23 /drivers/usb/host/xhci.h | |
| parent | 204b7793f2a9935e9a08524d0b4bb51b990d518e (diff) | |
| download | linux-e8b373326d8efcaf9ec1da8b618556c89bd5ffc4.tar.bz2 | |
xhci: replace xhci_read_64() with readq()
Function xhci_read_64() is used to read 64bit xHC registers residing in MMIO.
On 32bit systems, xHC registers need to be read with 32bit accesses by
reading first the lower 32bits and then the higher 32bits.
Replace all calls to xhci_read_64() with calls to readq() and include
asm-generic/io-64-nonatomic-lo-hi.h header file, so that if the system
is not 64bit, readq() will read registers in 32bit chunks with low-high order.
This is done to reduce code duplication since 64bit low-high read logic
is already implemented and to take advantage of inherent "atomic" 64bit
read operations on 64bit systems.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Diffstat (limited to 'drivers/usb/host/xhci.h')
| -rw-r--r-- | drivers/usb/host/xhci.h | 10 |
1 files changed, 2 insertions, 8 deletions
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 402d8743d245..5579b44379a4 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -28,6 +28,8 @@ #include <linux/kernel.h> #include <linux/usb/hcd.h> +#include <asm-generic/io-64-nonatomic-lo-hi.h> + /* Code sharing between pci-quirks and xhci hcd */ #include "xhci-ext-caps.h" #include "pci-quirks.h" @@ -1604,14 +1606,6 @@ static inline struct usb_hcd *xhci_to_hcd(struct xhci_hcd *xhci) * xHCI implementations that do not support 64-bit address pointers will ignore * the high dword, and write order is irrelevant. */ -static inline u64 xhci_read_64(const struct xhci_hcd *xhci, - __le64 __iomem *regs) -{ - __u32 __iomem *ptr = (__u32 __iomem *) regs; - u64 val_lo = readl(ptr); - u64 val_hi = readl(ptr + 1); - return val_lo + (val_hi << 32); -} static inline void xhci_write_64(struct xhci_hcd *xhci, const u64 val, __le64 __iomem *regs) { |