From: Johannes Zink <j.zink@xxxxxxxxxxxxxx> commit 4562c65ec852067c6196abdcf2d925f08841dcbc upstream. So far changing the period by just setting new period values while running did not work. The order as indicated by the publicly available reference manual of the i.MX8MP [1] indicates a sequence: * initiate the programming sequence * set the values for PPS period and start time * start the pulse train generation. This is currently not used in dwmac5_flex_pps_config(), which instead does: * initiate the programming sequence and immediately start the pulse train generation * set the values for PPS period and start time This caused the period values written not to take effect until the FlexPPS output was disabled and re-enabled again. This patch fix the order and allows the period to be set immediately. [1] https://www.nxp.com/webapp/Download?colCode=IMX8MPRM Fixes: 9a8a02c9d46d ("net: stmmac: Add Flexible PPS support") Signed-off-by: Johannes Zink <j.zink@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230210143937.3427483-1-j.zink@xxxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/dwmac5.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c @@ -541,9 +541,9 @@ int dwmac5_flex_pps_config(void __iomem return 0; } - val |= PPSCMDx(index, 0x2); val |= TRGTMODSELx(index, 0x2); val |= PPSEN0; + writel(val, ioaddr + MAC_PPS_CONTROL); writel(cfg->start.tv_sec, ioaddr + MAC_PPSx_TARGET_TIME_SEC(index)); @@ -568,6 +568,7 @@ int dwmac5_flex_pps_config(void __iomem writel(period - 1, ioaddr + MAC_PPSx_WIDTH(index)); /* Finally, activate it */ + val |= PPSCMDx(index, 0x2); writel(val, ioaddr + MAC_PPS_CONTROL); return 0; }
