ssb: Add support for block-I/O

This adds support for block based I/O to SSB.
This is needed in order to efficiently support PIO data
transfers to the card.
The block-I/O support is only compiled, if it's selected by the
weird driver that needs it. So there's no overhead for sane devices.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 102 insertions, 0 deletions

diff --git a/drivers/ssb/main.c b/drivers/ssb/main.c
index 3e58db7ef608..19ddd2bd1057 100644
--- a/drivers/ssb/main.c
+++ b/drivers/ssb/main.c
@@ -555,6 +555,55 @@ static u32 ssb_ssb_read32(struct ssb_device *dev, u16 offset)
         return readl(bus->mmio + offset);
 }
 
+#ifdef CONFIG_SSB_BLOCKIO
+static void ssb_ssb_block_read(struct ssb_device *dev, void *buffer,
+                               size_t count, u16 offset, u8 reg_width)
+{
+        struct ssb_bus *bus = dev->bus;
+        void __iomem *addr;
+
+        offset += dev->core_index * SSB_CORE_SIZE;
+        addr = bus->mmio + offset;
+
+        switch (reg_width) {
+        case sizeof(u8): {
+                u8 *buf = buffer;
+
+                while (count) {
+                        *buf = __raw_readb(addr);
+                        buf++;
+                        count--;
+                }
+                break;
+        }
+        case sizeof(u16): {
+                __le16 *buf = buffer;
+
+                SSB_WARN_ON(count & 1);
+                while (count) {
+                        *buf = (__force __le16)__raw_readw(addr);
+                        buf++;
+                        count -= 2;
+                }
+                break;
+        }
+        case sizeof(u32): {
+                __le32 *buf = buffer;
+
+                SSB_WARN_ON(count & 3);
+                while (count) {
+                        *buf = (__force __le32)__raw_readl(addr);
+                        buf++;
+                        count -= 4;
+                }
+                break;
+        }
+        default:
+                SSB_WARN_ON(1);
+        }
+}
+#endif /* CONFIG_SSB_BLOCKIO */
+
 static void ssb_ssb_write8(struct ssb_device *dev, u16 offset, u8 value)
 {
         struct ssb_bus *bus = dev->bus;
@@ -579,6 +628,55 @@ static void ssb_ssb_write32(struct ssb_device *dev, u16 offset, u32 value)
         writel(value, bus->mmio + offset);
 }
 
+#ifdef CONFIG_SSB_BLOCKIO
+static void ssb_ssb_block_write(struct ssb_device *dev, const void *buffer,
+                                size_t count, u16 offset, u8 reg_width)
+{
+        struct ssb_bus *bus = dev->bus;
+        void __iomem *addr;
+
+        offset += dev->core_index * SSB_CORE_SIZE;
+        addr = bus->mmio + offset;
+
+        switch (reg_width) {
+        case sizeof(u8): {
+                const u8 *buf = buffer;
+
+                while (count) {
+                        __raw_writeb(*buf, addr);
+                        buf++;
+                        count--;
+                }
+                break;
+        }
+        case sizeof(u16): {
+                const __le16 *buf = buffer;
+
+                SSB_WARN_ON(count & 1);
+                while (count) {
+                        __raw_writew((__force u16)(*buf), addr);
+                        buf++;
+                        count -= 2;
+                }
+                break;
+        }
+        case sizeof(u32): {
+                const __le32 *buf = buffer;
+
+                SSB_WARN_ON(count & 3);
+                while (count) {
+                        __raw_writel((__force u32)(*buf), addr);
+                        buf++;
+                        count -= 4;
+                }
+                break;
+        }
+        default:
+                SSB_WARN_ON(1);
+        }
+}
+#endif /* CONFIG_SSB_BLOCKIO */
+
 /* Ops for the plain SSB bus without a host-device (no PCI or PCMCIA). */
 static const struct ssb_bus_ops ssb_ssb_ops = {
         .read8          = ssb_ssb_read8,
@@ -587,6 +685,10 @@ static const struct ssb_bus_ops ssb_ssb_ops = {
         .write8         = ssb_ssb_write8,
         .write16        = ssb_ssb_write16,
         .write32        = ssb_ssb_write32,
+#ifdef CONFIG_SSB_BLOCKIO
+        .block_read     = ssb_ssb_block_read,
+        .block_write    = ssb_ssb_block_write,
+#endif
 };
 
 static int ssb_fetch_invariants(struct ssb_bus *bus,