pasemi: DMA engine management library

pasemi: DMA engine management library

Introduce a DMA management library to manage the various DMA resources
on the PA Semi SoCs. Since several drivers need to allocate these shared
resources, provide some abstractions as well as allocation/free functions
for channels, etc.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/include/asm-powerpc/pasemi_dma.h b/include/asm-powerpc/pasemi_dma.h
index 8ef80d8bdecd..b4526ff3a50d 100644
--- a/include/asm-powerpc/pasemi_dma.h
+++ b/include/asm-powerpc/pasemi_dma.h
@@ -33,11 +33,27 @@ struct pasdma_status {
  * device. Use the normal PCI config access functions for them.
  */
 enum {
+        PAS_DMA_CAP_TXCH  = 0x44,       /* Transmit Channel Info      */
+        PAS_DMA_CAP_RXCH  = 0x48,       /* Transmit Channel Info      */
+        PAS_DMA_CAP_IFI   = 0x4c,       /* Interface Info             */
         PAS_DMA_COM_TXCMD = 0x100,      /* Transmit Command Register  */
         PAS_DMA_COM_TXSTA = 0x104,      /* Transmit Status Register   */
         PAS_DMA_COM_RXCMD = 0x108,      /* Receive Command Register   */
         PAS_DMA_COM_RXSTA = 0x10c,      /* Receive Status Register    */
 };
+
+
+#define PAS_DMA_CAP_TXCH_TCHN_M 0x00ff0000 /* # of TX channels */
+#define PAS_DMA_CAP_TXCH_TCHN_S 16
+
+#define PAS_DMA_CAP_RXCH_RCHN_M 0x00ff0000 /* # of RX channels */
+#define PAS_DMA_CAP_RXCH_RCHN_S 16
+
+#define PAS_DMA_CAP_IFI_IOFF_M  0xff000000 /* Cfg reg for intf pointers */
+#define PAS_DMA_CAP_IFI_IOFF_S  24
+#define PAS_DMA_CAP_IFI_NIN_M   0x00ff0000 /* # of interfaces */
+#define PAS_DMA_CAP_IFI_NIN_S   16
+
 #define PAS_DMA_COM_TXCMD_EN    0x00000001 /* enable */
 #define PAS_DMA_COM_TXSTA_ACT   0x00000001 /* active */
 #define PAS_DMA_COM_RXCMD_EN    0x00000001 /* enable */
@@ -388,4 +404,64 @@ enum {
                                  CTRL_CMD_REG_M)
 
 
+
+/* Prototypes for the shared DMA functions in the platform code. */
+
+/* DMA TX Channel type. Right now only limitations used are event types 0/1,
+ * for event-triggered DMA transactions.
+ */
+
+enum pasemi_dmachan_type {
+        RXCHAN = 0,             /* Any RX chan */
+        TXCHAN = 1,             /* Any TX chan */
+        TXCHAN_EVT0 = 0x1001,   /* TX chan in event class 0 (chan 0-9) */
+        TXCHAN_EVT1 = 0x2001,   /* TX chan in event class 1 (chan 10-19) */
+};
+
+struct pasemi_dmachan {
+        int              chno;          /* Channel number */
+        enum pasemi_dmachan_type chan_type;     /* TX / RX */
+        u64             *status;        /* Ptr to cacheable status */
+        int              irq;           /* IRQ used by channel */
+        unsigned int     ring_size;     /* size of allocated ring */
+        dma_addr_t       ring_dma;      /* DMA address for ring */
+        u64             *ring_virt;     /* Virt address for ring */
+        void            *priv;          /* Ptr to start of client struct */
+};
+
+/* Read/write the different registers in the I/O Bridge, Ethernet
+ * and DMA Controller
+ */
+extern unsigned int pasemi_read_iob_reg(unsigned int reg);
+extern void pasemi_write_iob_reg(unsigned int reg, unsigned int val);
+
+extern unsigned int pasemi_read_mac_reg(int intf, unsigned int reg);
+extern void pasemi_write_mac_reg(int intf, unsigned int reg, unsigned int val);
+
+extern unsigned int pasemi_read_dma_reg(unsigned int reg);
+extern void pasemi_write_dma_reg(unsigned int reg, unsigned int val);
+
+/* Channel management routines */
+
+extern void *pasemi_dma_alloc_chan(enum pasemi_dmachan_type type,
+                                   int total_size, int offset);
+extern void pasemi_dma_free_chan(struct pasemi_dmachan *chan);
+
+extern void pasemi_dma_start_chan(const struct pasemi_dmachan *chan,
+                                  const u32 cmdsta);
+extern int pasemi_dma_stop_chan(const struct pasemi_dmachan *chan);
+
+/* Common routines to allocate rings and buffers */
+
+extern int pasemi_dma_alloc_ring(struct pasemi_dmachan *chan, int ring_size);
+extern void pasemi_dma_free_ring(struct pasemi_dmachan *chan);
+
+extern void *pasemi_dma_alloc_buf(struct pasemi_dmachan *chan, int size,
+                                  dma_addr_t *handle);
+extern void pasemi_dma_free_buf(struct pasemi_dmachan *chan, int size,
+                                dma_addr_t *handle);
+
+/* Initialize the library, must be called before any other functions */
+extern int pasemi_dma_init(void);
+
 #endif /* ASM_PASEMI_DMA_H */