ARM: S3C24XX: add dmaengine based dma-driver

A patchset in state Mainline for linux-kernel

From: Heiko Stuebner <heiko@...> Date: Wed, 18 Sep 2013 11:15:09 +0200

This series tries to provide a basic dmaengine driver for the s3c24xx SoCs to subsequently retire the old one with custom API. Since v4 an unnecessary second call to retrieve the dma cookie status was removed. Since v3 more smaller fixes were added, and memcpy operations now have a very simple mechanism to try to use higher transfer widths. Since v2 only some small fixes to the dma driver itself were added. Since v1 three big changes happened (appart from fixing received comments): For one the limitation of sg-lists to 1 element is gone.Secondly the specifics of the virtual channels (target bus, handshake, etc) are not encoded with channel ids but in the platformdata - making a later dt binding easier, as these informations can there be gathered by the xlate function. And lastly I also added a preliminary mechanism to handle the specific needs for the earlier variants of the driver. While s3c2443 and later can use any channel for any peripheral with just marking the target-peripheral-id in a register, earlier SoCs can only use specific channels and the target-ids also vary depending on the channel. Therefore on newer SoCs the chansel element only needs to contain the requested target-id, while on the older variants use it to encode both the valid channels and the channel-specific peripheral-id. On affected SoCs the target-id is always 3 bit wide, so we use these and an additional 4th bit to hold the valid state. As the older SoCs all have 4 dma channels this can live happily in an u16 element. The s3c24xx series will most likely not see any new offspring, but even if it happens any new model will probably use the newer more flexible variant of the dma controller, so this should not restrict anything in the future. Example: SDI is valid on channels 0, 2 and 3 - with varying hw request sources. For it the chansel field would look like ((BIT(3) | 1) << 3 * 4) | // channel 3, with request source 1 ((BIT(3) | 2) << 2 * 4) | // channel 2, with request source 2 ((BIT(3) | 2) << 0 * 4) // channel 0, with request source 2 Heiko Stuebner (4): ARM: S3C24XX: number the dma clocks dmaengine: add driver for Samsung s3c24xx SoCs ARM: S3C24XX: add platform-devices for new dma driver for s3c2412 and s3c2443 ARM: SAMSUNG: set s3c24xx_dma_filter for s3c64xx-spi0 device arch/arm/mach-s3c24xx/clock-s3c2412.c | 8 +- arch/arm/mach-s3c24xx/common-s3c2443.c | 12 +- arch/arm/mach-s3c24xx/common.c | 106 +++ arch/arm/mach-s3c24xx/common.h | 3 + arch/arm/mach-s3c24xx/mach-jive.c | 1 + arch/arm/mach-s3c24xx/mach-smdk2413.c | 1 + arch/arm/mach-s3c24xx/mach-smdk2416.c | 1 + arch/arm/mach-s3c24xx/mach-smdk2443.c | 1 + arch/arm/mach-s3c24xx/mach-vstms.c | 1 + arch/arm/plat-samsung/devs.c | 5 +- drivers/dma/Kconfig | 12 + drivers/dma/Makefile | 1 + drivers/dma/s3c24xx-dma.c | 1340 +++++++++++++++++++++++++++++ include/linux/platform_data/dma-s3c24xx.h | 43 + 14 files changed, 1524 insertions(+), 11 deletions(-) create mode 100644 drivers/dma/s3c24xx-dma.c create mode 100644 include/linux/platform_data/dma-s3c24xx.h --

Patches in this set


  • 4 individual patches
  • 1524 lines added
  • 11 lines removed

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