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From: Hans Andersson <haan@cellavision.se>
To: <mcoquelin.stm32@gmail.com>
Cc: alexandre.torgue@st.com, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org, davem@davemloft.net,
	joabreu@synopsys.com, peppe.cavallaro@st.com,
	Hans Andersson <hans.andersson@cellavision.se>,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] net: stmmac: Read user ID muliple times if needed.
Date: Wed, 2 Oct 2019 09:07:21 +0200	[thread overview]
Message-ID: <20191002070721.9916-1-haan@cellavision.se> (raw)

From: Hans Andersson <hans.andersson@cellavision.se>

When we read user ID / Synopsys ID we might still be in reset,
so read muliple times if needed.

Signed-off-by: Hans Andersson <hans.andersson@cellavision.se>
---
 drivers/net/ethernet/stmicro/stmmac/hwif.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.c b/drivers/net/ethernet/stmicro/stmmac/hwif.c
index 6c61b75..3347164 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.c
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.c
@@ -10,7 +10,16 @@
 
 static u32 stmmac_get_id(struct stmmac_priv *priv, u32 id_reg)
 {
-	u32 reg = readl(priv->ioaddr + id_reg);
+	u32 reg;
+	int i;
+
+	/* We might still be in reset when we read, */
+	/* so read multiple times if needed. */
+	for (i = 0; i < 10; i++) {
+		reg = readl(priv->ioaddr + id_reg);
+		if (reg)
+			break;
+	}
 
 	if (!reg) {
 		dev_info(priv->device, "Version ID not available\n");
-- 
2.17.1


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             reply	other threads:[~2019-10-02  7:08 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-02  7:07 Hans Andersson [this message]
2019-10-02  7:52 ` [PATCH] net: stmmac: Read user ID muliple times if needed Jose Abreu
2019-10-02  8:02   ` Hans Andersson
2019-10-02  8:08     ` Jose Abreu

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