On Wed, 05 Oct 2022 15:52:01 +0200, Jon Hunter wrote:
On 05/10/2022 13:29, Takashi Iwai wrote:
...
HDA playback is failing on -next for various Tegra boards. Bisect is point to this commit and reverting it fixes the problem. I was a bit puzzled why this change is causing a problem, but looking closer there is a difference between the previous code that was calling snd_hdac_stream_readb() and the new code that is calling snd_hdac_stream_readb_poll(). The function snd_hdac_stream_readb() calls snd_hdac_aligned_mmio() is see if the device has an aligned MMIO which Tegra does and then would call snd_hdac_aligned_read(). However, now the code always call readb() and this is breaking Tegra.
So it is either necessary to update snd_hdac_stream_readb_poll() to handle this or revert this change.
Does the patch below work?
thanks,
Takashi
-- 8< -- --- a/include/sound/hdaudio.h +++ b/include/sound/hdaudio.h @@ -592,8 +592,8 @@ int snd_hdac_get_stream_stripe_ctl(struct hdac_bus *bus, #define snd_hdac_stream_readb(dev, reg) \ snd_hdac_reg_readb((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg) #define snd_hdac_stream_readb_poll(dev, reg, val, cond, delay_us, timeout_us) \
- readb_poll_timeout((dev)->sd_addr + AZX_REG_ ## reg, val, cond, \
delay_us, timeout_us)
- read_poll_timeout(snd_hdac_reg_readb, val, cond, delay_us, timeout_us,\
false, (dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg)Amazingly it does not work. I would have thought that would, but it does not. I am a bit puzzled by that?
Interesting, it must be a subtle difference. What about passing true? It seems that the original code has the udelay(3) before the loop.
Takashi
-- 8< -- --- a/include/sound/hdaudio.h +++ b/include/sound/hdaudio.h @@ -592,8 +592,8 @@ int snd_hdac_get_stream_stripe_ctl(struct hdac_bus *bus, #define snd_hdac_stream_readb(dev, reg) \ snd_hdac_reg_readb((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg) #define snd_hdac_stream_readb_poll(dev, reg, val, cond, delay_us, timeout_us) \ - readb_poll_timeout((dev)->sd_addr + AZX_REG_ ## reg, val, cond, \ - delay_us, timeout_us) + read_poll_timeout(snd_hdac_reg_readb, val, cond, delay_us, timeout_us,\ + true, (dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg) #define snd_hdac_stream_readl_poll(dev, reg, val, cond, delay_us, timeout_us) \ readl_poll_timeout((dev)->sd_addr + AZX_REG_ ## reg, val, cond, \ delay_us, timeout_us)