On Fri, Jun 15, 2018 at 10:18:50AM +0900, Masahiro Yamada wrote: > 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> > --- > > Changes in v3: > - Change the patch order so that the bug-fix one comes the first > > Changes in v2: > - Split patches into sensible chunks > > .../devicetree/bindings/mtd/denali-nand.txt | 5 +++ > drivers/mtd/nand/raw/denali_dt.c | 49 ++++++++++++++++++++-- > 2 files changed, 50 insertions(+), 4 deletions(-) > > diff --git a/Documentation/devicetree/bindings/mtd/denali-nand.txt b/Documentation/devicetree/bindings/mtd/denali-nand.txt > index 0ee8edb..f33da87 100644 > --- a/Documentation/devicetree/bindings/mtd/denali-nand.txt > +++ b/Documentation/devicetree/bindings/mtd/denali-nand.txt > @@ -8,6 +8,9 @@ Required properties: > - reg : should contain registers location and length for data and reg. > - reg-names: Should contain the reg names "nand_data" and "denali_reg" > - interrupts : The interrupt number. > + - clocks: should contain phandle of the controller core clock, the bus > + interface clock, and the ECC circuit clock. > + - clock-names: should contain "nand", "nand_x", "ecc" The subject says "add more clocks", but it doesn't look like any clocks were supported before. Or documentation was missing? Please split bindings to a separate patch. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html