Return-Path: From: To: , , , CC: , , , , , Sean Wang , "Matthias Brugger" , Ulf Hansson , Weiyi Lu Subject: [PATCH v1 5/7] soc: mediatek: add a fixed wait for SRAM stable Date: Tue, 3 Apr 2018 15:15:55 +0800 Message-ID: <0fc10b2498c6dbe20141831c722c32cc74330d3d.1522736996.git.sean.wang@mediatek.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain List-ID: From: Sean Wang 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 Cc: Matthias Brugger Cc: Ulf Hansson Cc: Weiyi Lu --- 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; }; 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, }, }; -- 2.7.4