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aa7381876c
In chipidea IP RTL, there is a very limited design for siTD, the detail like below: There is no Max Packet Size at siTD, so it uses one constant for both Max Packet Size for packet and the packet size for the last transaction when considering schedule. If the ttctrl.ttha does not match against Hub Address field in siTD, this constant is 188 bytes, else this constant is 1023 bytes. If the ttctrl.ttha is non-zero value, RTL will use 188 as this constant, so it will lose the data if the packet size is larger than 188 bytes, eg, if we playback a wav which format is 48khz, 16 bits, 2 channels, the packet size will be 192bytes, but the controller will only send 188 bytes for this packet, the noise will be heared using USB audio card. The use case is single transaction, but higher frame rate. If the ttctr.ttha is zero value, we can send 1023 bytes within one transaction, but the controller will not accept the coming tranaction if it considers the schedule time is less than 1023 bytes. So the limitation is we can't schedule as many as transactions within frame. If the total bytes is already 256 bytes for previous transactions within frame, it can't accept another transaction. The use case is multiple transactions, but less frame rate. Signed-off-by: Peter Chen <peter.chen@nxp.com> |
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| .. | ||
| bits.h | ||
| ci.h | ||
| ci_hdrc_imx.c | ||
| ci_hdrc_imx.h | ||
| ci_hdrc_msm.c | ||
| ci_hdrc_pci.c | ||
| ci_hdrc_usb2.c | ||
| ci_hdrc_zevio.c | ||
| core.c | ||
| debug.c | ||
| host.c | ||
| host.h | ||
| Kconfig | ||
| Makefile | ||
| otg.c | ||
| otg.h | ||
| otg_fsm.c | ||
| otg_fsm.h | ||
| udc.c | ||
| udc.h | ||
| usbmisc_imx.c | ||