From: Stanley Chu <stanley.chu@mediatek.com>
To: <linux-scsi@vger.kernel.org>, <martin.petersen@oracle.com>,
<avri.altman@wdc.com>, <alim.akhtar@samsung.com>,
<jejb@linux.ibm.com>
Cc: pengshun.zhao@mediatek.com,
Stanley Chu <stanley.chu@mediatek.com>,
bvanassche@acm.org, andy.teng@mediatek.com, cc.chou@mediatek.com,
chun-hung.wu@mediatek.com, kuohong.wang@mediatek.com,
linux-kernel@vger.kernel.org, cang@codeaurora.org,
linux-mediatek@lists.infradead.org, peter.wang@mediatek.com,
matthias.bgg@gmail.com, beanhuo@micron.com,
chaotian.jing@mediatek.com, linux-arm-kernel@lists.infradead.org,
asutoshd@codeaurora.org
Subject: [PATCH v2 2/5] scsi: ufs-mediatek: Do not gate clocks if auto-hibern8 is not entered yet
Date: Fri, 29 May 2020 17:23:07 +0800 [thread overview]
Message-ID: <20200529092310.1106-3-stanley.chu@mediatek.com> (raw)
In-Reply-To: <20200529092310.1106-1-stanley.chu@mediatek.com>
There are some chances that link enters hibern8 lately by auto-hibern8
scheme during the clock-gating flow. Clocks shall not be gated if link
is still active otherwise host or device may hang.
Fix this by returning error code to the caller __ufshcd_setup_clocks()
to skip gating clocks there if link is not confirmed in hibern8
state yet.
Also allow some waiting time for the hibern8 state transition.
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Andy Teng <andy.teng@mediatek.com>
---
drivers/scsi/ufs/ufs-mediatek.c | 36 ++++++++++++++++++++++++---------
1 file changed, 27 insertions(+), 9 deletions(-)
diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
index 523ee5573921..3c85f5e97dea 100644
--- a/drivers/scsi/ufs/ufs-mediatek.c
+++ b/drivers/scsi/ufs/ufs-mediatek.c
@@ -178,15 +178,30 @@ static void ufs_mtk_setup_ref_clk_wait_us(struct ufs_hba *hba,
host->ref_clk_ungating_wait_us = ungating_us;
}
-static u32 ufs_mtk_link_get_state(struct ufs_hba *hba)
+int ufs_mtk_wait_link_state(struct ufs_hba *hba, u32 state,
+ unsigned long max_wait_ms)
{
+ ktime_t timeout, time_checked;
u32 val;
- ufshcd_writel(hba, 0x20, REG_UFS_DEBUG_SEL);
- val = ufshcd_readl(hba, REG_UFS_PROBE);
- val = val >> 28;
+ timeout = ktime_add_us(ktime_get(), ms_to_ktime(max_wait_ms));
+ do {
+ time_checked = ktime_get();
+ ufshcd_writel(hba, 0x20, REG_UFS_DEBUG_SEL);
+ val = ufshcd_readl(hba, REG_UFS_PROBE);
+ val = val >> 28;
+
+ if (val == state)
+ return 0;
- return val;
+ /* Sleep for max. 200us */
+ usleep_range(100, 200);
+ } while (ktime_before(time_checked, timeout));
+
+ if (val == state)
+ return 0;
+
+ return -ETIMEDOUT;
}
/**
@@ -221,10 +236,13 @@ static int ufs_mtk_setup_clocks(struct ufs_hba *hba, bool on,
* triggered by Auto-Hibern8.
*/
if (!ufshcd_can_hibern8_during_gating(hba) &&
- ufshcd_is_auto_hibern8_enabled(hba) &&
- ufs_mtk_link_get_state(hba) ==
- VS_LINK_HIBERN8)
- ufs_mtk_setup_ref_clk(hba, on);
+ ufshcd_is_auto_hibern8_enabled(hba)) {
+ ret = ufs_mtk_wait_link_state(hba,
+ VS_LINK_HIBERN8,
+ 15);
+ if (!ret)
+ ufs_mtk_setup_ref_clk(hba, on);
+ }
}
} else if (on && status == POST_CHANGE) {
ret = phy_power_on(host->mphy);
--
2.18.0
_______________________________________________
Linux-mediatek mailing list
Linux-mediatek@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-mediatek
next prev parent reply other threads:[~2020-05-29 9:25 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-29 9:23 [PATCH v2 0/5] scsi: ufs-mediatek: Fix clk-gating and introduce low-power mode for vccq2 Stanley Chu
2020-05-29 9:23 ` [PATCH v2 1/5] scsi: ufs-mediatek: Fix imprecise waiting time for ref-clk control Stanley Chu
2020-05-31 7:10 ` Avri Altman
2020-05-31 13:45 ` Stanley Chu
2020-05-29 9:23 ` Stanley Chu [this message]
2020-05-29 9:23 ` [PATCH v2 3/5] scsi: ufs-mediatek: Introduce low-power mode for device power supply Stanley Chu
2020-05-29 9:23 ` [PATCH v2 4/5] scsi: ufs-mediatek: Fix unbalanced clock on/off Stanley Chu
2020-05-29 9:23 ` [PATCH v2 5/5] scsi: ufs-mediatek: Allow unbound mphy Stanley Chu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200529092310.1106-3-stanley.chu@mediatek.com \
--to=stanley.chu@mediatek.com \
--cc=alim.akhtar@samsung.com \
--cc=andy.teng@mediatek.com \
--cc=asutoshd@codeaurora.org \
--cc=avri.altman@wdc.com \
--cc=beanhuo@micron.com \
--cc=bvanassche@acm.org \
--cc=cang@codeaurora.org \
--cc=cc.chou@mediatek.com \
--cc=chaotian.jing@mediatek.com \
--cc=chun-hung.wu@mediatek.com \
--cc=jejb@linux.ibm.com \
--cc=kuohong.wang@mediatek.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=linux-scsi@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=matthias.bgg@gmail.com \
--cc=pengshun.zhao@mediatek.com \
--cc=peter.wang@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).