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  1. 20 12月, 2016 1 次提交
  3. 15 12月, 2016 1 次提交
    • S
      spi: sh-msiof: Add R-Car Gen 2 and 3 fallback bindings · 4286db84
      由 Simon Horman 提交于 
      In the case of Renesas R-Car hardware we know that there are generations of
SoCs, e.g. Gen 2 and Gen 3. But beyond that it's not clear what the
relationship between IP blocks might be. For example, I believe that
r8a7790 is older than r8a7791 but that doesn't imply that the latter is a
descendant of the former or vice versa.

We can, however, by examining the documentation and behaviour of the
hardware at run-time observe that the current driver implementation appears
to be compatible with the IP blocks on SoCs within a given generation.

For the above reasons and convenience when enabling new SoCs a
per-generation fallback compatibility string scheme is being adopted for
drivers for Renesas SoCs.

Also:
* Deprecate renesas,sh-msiof. It seems poorly named as it is only
  compatible with SH-Mobile. It also appears unused in mainline.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@kernel.org>
      4286db84
  5. 22 11月, 2016 1 次提交
  7. 05 8月, 2016 1 次提交
  9. 22 6月, 2016 1 次提交
  11. 31 8月, 2015 1 次提交
  13. 07 7月, 2015 1 次提交
  15. 02 5月, 2015 1 次提交
  17. 23 2月, 2015 1 次提交
  19. 05 2月, 2015 1 次提交
  21. 03 2月, 2015 1 次提交
  23. 08 1月, 2015 1 次提交
  25. 06 1月, 2015 1 次提交
  27. 24 12月, 2014 1 次提交
  29. 16 12月, 2014 1 次提交
  31. 20 10月, 2014 1 次提交
  33. 31 8月, 2014 1 次提交
  35. 29 8月, 2014 1 次提交
  37. 17 8月, 2014 5 次提交
  39. 17 7月, 2014 2 次提交
  41. 01 7月, 2014 1 次提交
    • G
      spi: sh-msiof: Add DMA support · b0d0ce8b
      由 Geert Uytterhoeven 提交于 
      Add DMA support to the MSIOF driver using platform data.

As MSIOF DMA is limited to 32-bit words (requiring byte/wordswapping for
smaller wordsizes), and the group length is limited to 256 words, DMA is
performed on two fixed pages, allocated and mapped at driver initialization
time.

Performance figures (in Mbps) on r8a7791/koelsch at different SPI clock
frequencies for 1024-byte and 4096-byte transfers:

                   1024 bytes           4096 bytes
  -  3.25 MHz: PIO  2.1, DMA  2.6 | PIO  2.8, DMA  3.1
  -  6.5  MHz: PIO  3.2, DMA  4.4 | PIO  5.0, DMA  5.9
  - 13    MHz: PIO  4.2, DMA  6.6 | PIO  8.2, DMA 10.7
  - 26    MHz: PIO  5.9, DMA 10.4 | PIO 12.4, DMA 18.4

Note that DMA is only faster than PIO for transfers that exceed the FIFO
size (typically 64 words / 256 bytes).

Also note that large transfers (larger than the group length for DMA, or
larger than the FIFO size for PIO), should use cs-gpio (with the
appropriate pinmux setup), as the hardware chipselect will be deasserted in
between chunks.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>
      b0d0ce8b
  43. 21 6月, 2014 4 次提交
  45. 06 6月, 2014 1 次提交
  47. 30 4月, 2014 1 次提交
  49. 11 3月, 2014 1 次提交
  51. 03 3月, 2014 1 次提交
  53. 27 2月, 2014 6 次提交