Hi Enric, Am Donnerstag, 19. April 2018, 13:30:16 CEST schrieb Enric Balletbo i Serra: > On 19/04/18 13:10, Heiko Stuebner wrote: > > Am Donnerstag, 19. April 2018, 12:40:15 CEST schrieb Enric Balletbo i Serra: > >> DDR3 SDRAM Standard (JESD79-3F) defines some standard speed bins for > >> DDR3 memories. The devfreq/rk3399_dmc.txt binding refers to this file > >> which does not exist, so add a ddr.h file with the standard speed bins > >> for DDR3. > >> > >> Fixes: c1ceb8f7c167 (Documentation: bindings: add dt documentation for rk3399 dmc) > >> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx> > >> --- > >> > >> include/dt-bindings/clock/ddr.h | 34 +++++++++++++++++++++++++++++++++ > >> 1 file changed, 34 insertions(+) > >> create mode 100644 include/dt-bindings/clock/ddr.h > >> > >> diff --git a/include/dt-bindings/clock/ddr.h b/include/dt-bindings/clock/ddr.h > >> new file mode 100644 > >> index 000000000000..506aef7e609e > >> --- /dev/null > >> +++ b/include/dt-bindings/clock/ddr.h > >> @@ -0,0 +1,34 @@ > >> +/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */ > >> + > >> +#ifndef DT_BINDINGS_DDR_H > >> +#define DT_BINDINGS_DDR_H > >> + > >> +/* DDR3-800 Standard Speed Bins */ > >> +#define DDR3_800D 15 > >> +#define DDR3_800E 18 > >> +/* DDR3-1066 Standard Speed Bins */ > >> +#define DDR3_1066E 18 > >> +#define DDR3_1066F 21 > >> +#define DDR3_1066G 24 > > > > looking at the mentioned jedec standard, I don't see where these numerical > > values are defined in the standard itself. [I may be blind though] > > > > Damm it. No, you're not blind. I did an horrible mistake adding an old version > of this file. It's wrong, that is supposed to be there is DDR3 table available > in the ATF [1] not this. Mistakes can always happen ... so no problem :-) . > /* 5-5-5 */ > DDR3_800D = 0, > /* 6-6-6 */ > DDR3_800E = 1, > /* 6-6-6 */ > DDR3_1066E = 2, > /* 7-7-7 */ > DDR3_1066F = 3, > ... > > The value is passed directly to the ATF so the above values are the correct. > > One question that I have on my mind is if this file should be called as is or if > will be better name as atf-ddr.h or something like that. > ddr.h -> atf-ddr.h The more interesting question would be if this isn't a very much rockchip or even rk3399-specific scheme. So such a generic header name looks very much out of place (also including the very generic constant names). So far the only upstream ATF implementation is for the rk3399. Heiko > > [1] > https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/rockchip/rk3399/drivers/dram/dram_spec_timing.h > > Sorry about that. Guess it's needed a v2 but let's wait a little bit for if more > discussion arises. > > Best regards, > Enric > > > Could you explain a bit more where these numerical values are coming from? > > > > > > Thanks > > Heiko > > > > -- 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
