On Thu, 2018-04-19 at 12:33 +0200, Matthias Brugger wrote:
>
> On 04/03/2018 09:15 AM, sean.wang@xxxxxxxxxxxx wrote:
> > From: Sean Wang <sean.wang@xxxxxxxxxxxx>
> >
> > MT7622_POWER_DOMAIN_WB doesn't send an ACK when its managed SRAM becomes
> > stable, which is not like the behavior the other power domains should
> > have. Therefore, it's necessary for such a power domain to have a fixed
> > and well-predefined duration to wait until its managed SRAM can be allowed
> > to access by all functions running on the top.
> >
> > Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx>
> > Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> > Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > Cc: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
> > ---
> > drivers/soc/mediatek/mtk-scpsys.c | 17 ++++++++++++-----
> > 1 file changed, 12 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
> > index f9b7248..19aceb8 100644
> > --- a/drivers/soc/mediatek/mtk-scpsys.c
> > +++ b/drivers/soc/mediatek/mtk-scpsys.c
> > @@ -121,6 +121,7 @@ struct scp_domain_data {
> > u32 bus_prot_mask;
> > enum clk_id clk_id[MAX_CLKS];
> > bool active_wakeup;
> > + u32 us_sram_fwait;
>
> Before adding more and more fields to scp_domain_data which get checked in if's,
> I'd prefer to add a caps field used for bus_prot_mask, active_wakeup in a first
> patch and add the cap FORCE_WAIT in a second patch.
>
> Can you help to implement this Sean, or shall I give it a try?
>
Sure, I have a willing to do and then see if you're also fond of it.
thanks!
> Regards,
> Matthias
>
> > };
> >
> > struct scp;
> > @@ -234,11 +235,16 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> > val &= ~scpd->data->sram_pdn_bits;
> > writel(val, ctl_addr);
> >
> > - /* wait until SRAM_PDN_ACK all 0 */
> > - ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == 0,
> > - MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> > - if (ret < 0)
> > - goto err_pwr_ack;
> > + /* Either wait until SRAM_PDN_ACK all 0 or have a force wait */
> > + if (!scpd->data->us_sram_fwait) {
> > + ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == 0,
> > + MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
> > + if (ret < 0)
> > + goto err_pwr_ack;
> > + } else {
> > + usleep_range(scpd->data->us_sram_fwait,
> > + scpd->data->us_sram_fwait + 100);
> > + };
> >
> > if (scpd->data->bus_prot_mask) {
> > ret = mtk_infracfg_clear_bus_protection(scp->infracfg,
> > @@ -783,6 +789,7 @@ static const struct scp_domain_data scp_domain_data_mt7622[] = {
> > .clk_id = {CLK_NONE},
> > .bus_prot_mask = MT7622_TOP_AXI_PROT_EN_WB,
> > .active_wakeup = true,
> > + .us_sram_fwait = 12000,
> > },
> > };
> >
> >
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