Am Freitag, 15. Juni 2018, 03:18:50 CEST schrieb Masahiro Yamada: > According to the Denali User's Guide, this IP needs three clocks: > > - clk: controller core clock > > - clk_x: bus interface clock > > - ecc_clk: clock at which ECC circuitry is run > > Currently, denali_dt.c requires a single anonymous clock and its > frequency. However, the driver needs to get the frequency of "clk_x" > not "clk". This is confusing because people tend to assume the > anonymous clock means the core clock. In fact, I got a report of > SOCFPGA breakage because the timing parameters are calculated based > on a wrong frequency. > > Instead of the cheesy implementation, the clocks in the real hardware > should be represented in the driver and the DT-binding. > > However, adding new clocks would break the existing platforms. For the > backward compatibility, the driver still accepts a single clock just as > before. If clk_x is missing, clk_x_rate is set to a hardcoded value. > This is fine for existing DT of Socionext UniPhier, and also fixes the > issue of Altera (Intel) SOCFPGA because both platforms use 200 MHz for > the bus interface clock. > > Fixes: 1bb88666775e ("mtd: nand: denali: handle timing parameters by setup_data_interface()") > Cc: linux-stable <stable@xxxxxxxxxxxxxxx> #4.14+ > Reported-by: Richard Weinberger <richard@xxxxxx> > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Reviewed-by: Richard Weinberger <richard@xxxxxx> Reported-by: Philipp Rosenberger <p.rosenberger@xxxxxxxxxxxxx> Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html