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authorFurquan Shaikh <furquan@chromium.org>2017-04-19 19:27:28 -0700
committerMartin Roth <martinroth@google.com>2017-05-05 23:42:19 +0200
commitde705fa1f470683b9ea4ad91c1a9ae5a98942612 (patch)
tree60873b2b6772bf459cd8db2f171ae7711d507b02 /src/include
parentf1db5fdb4d03b4766cf23e4b04a05b0fc05586a0 (diff)
downloadcoreboot-de705fa1f470683b9ea4ad91c1a9ae5a98942612.tar.xz
drivers/spi: Re-factor spi_crop_chunk
spi_crop_chunk is a property of the SPI controller since it depends upon the maximum transfer size that is supported by the controller. Also, it is possible to implement this within spi-generic layer by obtaining following parameters from the controller: 1. max_xfer_size: Maximum transfer size supported by the controller (Size of 0 indicates invalid size, and unlimited transfer size is indicated by UINT32_MAX.) 2. deduct_cmd_len: Whether cmd_len needs to be deducted from the max_xfer_size to determine max data size that can be transferred. (This is used by the amd boards.) Change-Id: I81c199413f879c664682088e93bfa3f91c6a46e5 Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/19386 Reviewed-by: Aaron Durbin <adurbin@chromium.org> Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Tested-by: coreboot org <coreboot.org@gmail.com>
Diffstat (limited to 'src/include')
-rw-r--r--src/include/spi-generic.h36
1 files changed, 29 insertions, 7 deletions
diff --git a/src/include/spi-generic.h b/src/include/spi-generic.h
index 7d957a0d9c..56353bb692 100644
--- a/src/include/spi-generic.h
+++ b/src/include/spi-generic.h
@@ -87,14 +87,27 @@ struct spi_cfg {
unsigned int data_bit_length;
};
+/*
+ * If there is no limit on the maximum transfer size for the controller,
+ * max_xfer_size can be set to SPI_CTRLR_DEFAULT_MAX_XFER_SIZE which is equal to
+ * UINT32_MAX.
+ */
+#define SPI_CTRLR_DEFAULT_MAX_XFER_SIZE (UINT32_MAX)
+
/*-----------------------------------------------------------------------
- * Representation of a SPI contoller.
+ * Representation of a SPI controller.
+ *
+ * claim_bus: Claim SPI bus and prepare for communication.
+ * release_bus: Release SPI bus.
+ * setup: Setup given SPI device bus.
+ * xfer: Perform one SPI transfer operation.
+ * xfer_vector: Vector of SPI transfer operations.
+ * max_xfer_size: Maximum transfer size supported by the controller
+ * (0 = invalid,
+ * SPI_CTRLR_DEFAULT_MAX_XFER_SIZE = unlimited)
+ * deduct_cmd_len: Whether cmd_len should be deducted from max_xfer_size
+ * when calculating max_data_size
*
- * claim_bus: Claim SPI bus and prepare for communication.
- * release_bus: Release SPI bus.
- * setup: Setup given SPI device bus.
- * xfer: Perform one SPI transfer operation.
- * xfer_vector: Vector of SPI transfer operations.
*/
struct spi_ctrlr {
int (*claim_bus)(const struct spi_slave *slave);
@@ -104,6 +117,8 @@ struct spi_ctrlr {
size_t bytesout, void *din, size_t bytesin);
int (*xfer_vector)(const struct spi_slave *slave,
struct spi_op vectors[], size_t count);
+ uint32_t max_xfer_size;
+ bool deduct_cmd_len;
};
/*-----------------------------------------------------------------------
@@ -212,7 +227,14 @@ int spi_xfer(const struct spi_slave *slave, const void *dout, size_t bytesout,
int spi_xfer_vector(const struct spi_slave *slave,
struct spi_op vectors[], size_t count);
-unsigned int spi_crop_chunk(unsigned int cmd_len, unsigned int buf_len);
+/*-----------------------------------------------------------------------
+ * Given command length and length of remaining data, return the maximum data
+ * that can be transferred in next spi_xfer.
+ *
+ * Returns: 0 on error, non-zero data size that can be xfered on success.
+ */
+unsigned int spi_crop_chunk(const struct spi_slave *slave, unsigned int cmd_len,
+ unsigned int buf_len);
/*-----------------------------------------------------------------------
* Write 8 bits, then read 8 bits.