On 04/03/2018 09:15 AM, [email protected] wrote:
> From: Sean Wang <[email protected]>
>
> 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 <[email protected]>
> Cc: Matthias Brugger <[email protected]>
> Cc: Ulf Hansson <[email protected]>
> Cc: Weiyi Lu <[email protected]>
> ---
> 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?
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,
> },
> };
>
>
