[PATCHv2 2/6] dw_dmac: fill optional encoded parameters in register structure

From: Andy Shevchenko
Date: Fri Sep 21 2012 - 08:07:07 EST


There is a block of the registers that are optional. However, if enabled they
contain useful information about the controller hardware configuration. We will
use this piece of data to autoconfigure the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/dma/dw_dmac_regs.h | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h
index f6d92d7..8a3a81a 100644
--- a/drivers/dma/dw_dmac_regs.h
+++ b/drivers/dma/dw_dmac_regs.h
@@ -82,9 +82,39 @@ struct dw_dma_regs {
DW_REG(ID);
DW_REG(TEST);

+ /* reserved */
+ DW_REG(__reserved0);
+ DW_REG(__reserved1);
+
/* optional encoded params, 0x3c8..0x3f7 */
+ u32 __reserved;
+
+ /* per-channel configuration registers */
+ u32 DWC_PARAMS[DW_DMA_MAX_NR_CHANNELS];
+ u32 MULTI_BLK_TYPE;
+ u32 MAX_BLK_SIZE;
+
+ /* top-level parameters */
+ u32 DW_PARAMS;
};

+/* To access the registers in early stage of probe */
+#define dma_read_byaddr(addr, name) \
+ readl((addr) + offsetof(struct dw_dma_regs, name))
+
+/* Bitfields in DW_PARAMS */
+#define DW_PARAMS_NR_CHAN 8 /* number of channels */
+#define DW_PARAMS_NR_MASTER 11 /* number of AHB masters */
+#define DW_PARAMS_DATA_WIDTH(n) (15 + 2 * (n))
+#define DW_PARAMS_DATA_WIDTH1 15 /* master 1 data width */
+#define DW_PARAMS_DATA_WIDTH2 17 /* master 2 data width */
+#define DW_PARAMS_DATA_WIDTH3 19 /* master 3 data width */
+#define DW_PARAMS_DATA_WIDTH4 21 /* master 4 data width */
+#define DW_PARAMS_EN 28 /* encoded parameters */
+
+/* Bitfields in DWC_PARAMS */
+#define DWC_PARAMS_MBLK_EN 11 /* multi block transfer */
+
/* Bitfields in CTL_LO */
#define DWC_CTLL_INT_EN (1 << 0) /* irqs enabled? */
#define DWC_CTLL_DST_WIDTH(n) ((n)<<1) /* bytes per element */
--
1.7.10.4

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