Hi Nicolin,
On Wed, Jan 8, 2014 at 3:04 AM, Nicolin Chen Guangyu.Chen@freescale.com wrote:
I think it is impossible to run SDMA without firmware, which stores all the scripts we need, including Audio's one. Although the upstream kernel doesn't have firmware, the reason why you were able to run audio playback is because you have the firmware in your rootfs. So since the driver's upgraded, it's plausible for us to upgrade the firmware as well. But I
No, this is not correct.
Please see this commit from Sascha:
commit dcfec3c09890120d86d4e86887074c 76763075ca Author: Sascha Hauer s.hauer@pengutronix.de Date: Tue Aug 20 10:04:32 2013 +0200
dma: imx-sdma: Add ROM script addresses to driver
This adds the ROM script addresses for i.MX25, i.MX5x and i.MX6 to the SDMA driver needed for the driver to work without additional firmware.
The ROM script addresses are SoC specific and in some cases even tapeout specific. This patch adds the ROM script addresses only for SoCs which do not have a tapeout specific SDMA ROM, because currently it's unclear how this case should be handled.
Signed-off-by: Sascha Hauer s.hauer@pengutronix.de Acked-by: Shawn Guo shawn.guo@linaro.org Signed-off-by: Vinod Koul vinod.koul@intel.com
It allows audio to be played without any additional SDMA firmware.
Please try running 3.13-rc7 without the SDMA firmware and linux-next without firmware and you will get the difference: 3.13-rc7 will play the audio just fine, but linux-next will crash the system.
Regards,
Fabio Estevam