staging: gasket: core: switch to relaxed memory-mapped I/O

Use of readl() is deprecated; readl_relaxed() with appropriate memory
barriers is preferred.  Switch to relaxed reads and writes for better
performance as well.  Memory barriers required for I/O vs. normal
memory access on Apex devices have already been explicitly coded in the
page table routines.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gasket/gasket_core.h

@@ -590,25 +590,25 @@ const char *gasket_num_name_lookup(uint num,
 static inline ulong gasket_dev_read_64(struct gasket_dev *gasket_dev, int bar,
 				       ulong location)
 {
-	return readq(&gasket_dev->bar_data[bar].virt_base[location]);
+	return readq_relaxed(&gasket_dev->bar_data[bar].virt_base[location]);
 }
 
 static inline void gasket_dev_write_64(struct gasket_dev *dev, u64 value,
 				       int bar, ulong location)
 {
-	writeq(value, &dev->bar_data[bar].virt_base[location]);
+	writeq_relaxed(value, &dev->bar_data[bar].virt_base[location]);
 }
 
 static inline void gasket_dev_write_32(struct gasket_dev *dev, u32 value,
 				       int bar, ulong location)
 {
-	writel(value, &dev->bar_data[bar].virt_base[location]);
+	writel_relaxed(value, &dev->bar_data[bar].virt_base[location]);
 }
 
 static inline u32 gasket_dev_read_32(struct gasket_dev *dev, int bar,
 				     ulong location)
 {
-	return readl(&dev->bar_data[bar].virt_base[location]);
+	return readl_relaxed(&dev->bar_data[bar].virt_base[location]);
 }
 
 static inline void gasket_read_modify_write_64(struct gasket_dev *dev, int bar,