On Thu, 28 May 2015, Dinh Nguyen wrote:
> On 05/27/2015 03:25 PM, atull wrote:
> > On Tue, 26 May 2015, Dinh Nguyen wrote:
> >
> >> Hi Alan,
> >>
> >> On 5/22/15 1:02 PM, Alan Tull wrote:
> >>> Add code that requests that the sdr controller go into
> >>> self-refresh mode. This code is run from ocram.
> >>>
> >>> This patch assumes that u-boot has already configured sdr:
> >>> sdr.ctrlcfg.lowpwreq.selfrfshmask = 3
> >>> sdr.ctrlcfg.lowpwrtiming.clkdisablecycles = 8
> >>> sdr.ctrlcfg.dramtiming4.selfrfshexit = 512
> >>>
> >>> Suspend-to-RAM and EDAC support are mutually exclusive on SOCFPGA
> >>> platforms. CONFIG_SOCFPGA_SUSPEND enables suspend-to-RAM and
> >>> prevents selecting CONFIG_EDAC_ALTERA_MC.
> >>>
> >>> How to suspend to ram:
> >>> $ echo enabled > \
> >>> /sys/devices/soc/ffc02000.serial0/tty/ttyS0/power/wakeup
> >>>
> >>> $ echo -n mem > /sys/power/state
> >>>
> >>> Signed-off-by: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>
> >>> Cc: Pavel Machek <pavel@xxxxxxx>
> >>> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> >>> Cc: Dinh Nguyen <dinguyen@xxxxxxxxxxxxxxxxxxxxx>
> >>> Cc: Steffen Trumtrar <s.trumtrar@xxxxxxxxxxxxxx>
> >>> ---
> >>> v2: use Generic on-chip SRAM driver to allocate ocram
> >>> rm fncpy_align since generic allocator handles alignment
> >>> check __arm_ioremap_exec return code
> >>> check for NULL pointers
> >>> add a comment regarding sdram controller configuration
> >>> v3: fix renamed #define
> >>> propagate socfpga_setup_ocram_self_refresh error code
> >>> v4: Kconfig: don't need to select GENERIC_ALLOCATER
> >>> add CONFIG_SOCFPGA_SUSPEND
> >>> make s2r and EDAC support mutually exclusive
> >>> socfpga.c: add sdr_ctl_base_addr
> >>> return error if ocram not available in device tree
> >>> update copyright years
> >>> ---
> >>
> >> <snip>
> >>
> >>> +
> >>> +static int socfpga_pm_suspend(unsigned long arg)
> >>> +{
> >>> + u32 ret;
> >>> +
> >>> + if (!sdr_ctl_base_addr || !socfpga_scu_base_addr)
> >>> + return -EFAULT;
> >>> +
> >>> + ret = socfpga_sdram_self_refresh_in_ocram(
> >>> + (u32)sdr_ctl_base_addr, (u32)socfpga_scu_base_addr);
> >>> +
> >>
> >> I had a patch that removed socfpga_scu_base_addr from being a global and
> >> just a local variable in:
> >>
> >> f6e14376fb20 ARM: socfpga: use of_iomap to map the SCU
> >>
> >> This patch will be in v4.2 and is currently in arm-soc/next or
> >> at my fork: kernel/git/dinguyen/linux.git socfpga_for_next_arria10
> >>
> >> So you will either need to make socfpga_scu_base_addr global again, or
> >> you can use the asm instruction to get the SCU base addr.
> >>
> >> Sorry about that..
> >>
> >> Dinh
> >>
> >
> > I can't make socfpga_scu_base_addr a global from platsmp.c since that file
> > may or may not be compiled in.
>
> Ah, okay..
> >
> > That leaves me with the option of adding the code that was removed from
> > socfpga.c back where it was or taking that same code moving it to pm.c
> >
>
> I think you only need the scu base address in
> socfpga_sdram_self_refresh(), so you can probably just use the single
> line assembly code to get it there.
>
> Dinh
>
I realized that I don't need to touch the scu self refresh bit at all
here. It's handled in scu_enable().
Alan
--
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
