RE: [PATCH 10/10] ravb: Initialize GbEthernet E-MAC

-----Original Message-----
From: Sergey Shtylyov <redacted>
Sent: 04 October 2021 19:56
To: Biju Das <biju.das.jz@bp.renesas.com>; David S. Miller
[off-list ref]; Jakub Kicinski [off-list ref]
Cc: Sergei Shtylyov <redacted>; Geert Uytterhoeven
[off-list ref]; Sergey Shtylyov [off-list ref]; Adam
Ford [off-list ref]; Andrew Lunn [off-list ref]; Yuusuke Ashizuka
[off-list ref]; Yoshihiro Shimoda
[off-list ref]; netdev@vger.kernel.org; linux-renesas-
soc@vger.kernel.org; Chris Paterson [off-list ref]; Biju
Das [off-list ref]; Prabhakar Mahadev Lad <prabhakar.mahadev-
lad.rj@bp.renesas.com>
Subject: Re: [PATCH 10/10] ravb: Initialize GbEthernet E-MAC

On 10/1/21 6:06 PM, Biju Das wrote:

quoted

Initialize GbEthernet E-MAC found on RZ/G2L SoC.
This patch also renames ravb_set_rate to ravb_set_rate_rcar and
ravb_rcar_emac_init to ravb_emac_init_rcar to be consistent with the
naming convention used in sh_eth driver.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
RFC->v1:
 * Moved CSR0 intialization to later patch.
 * started using ravb_modify for initializing link registers.
---
 drivers/net/ethernet/renesas/ravb.h      | 20 +++++++--
 drivers/net/ethernet/renesas/ravb_main.c | 55
++++++++++++++++++++----
 2 files changed, 62 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h

b/drivers/net/ethernet/renesas/ravb.h
index d83d3b4f3f5f..5dc1324786e0 100644

--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h

[...]

quoted

@@ -824,6 +826,7 @@ enum ECSR_BIT {
 	ECSR_MPD	= 0x00000002,
 	ECSR_LCHNG	= 0x00000004,
 	ECSR_PHYI	= 0x00000008,
+	ECSR_PFRI	= 0x00000010,

   Documented on gen3 and RZ/G2L only?

[...]

quoted

diff --git a/drivers/net/ethernet/renesas/ravb_main.c

b/drivers/net/ethernet/renesas/ravb_main.c
index 3e694738e683..9a4888543384 100644

--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c

[...]

quoted

@@ -449,10 +461,35 @@ static int ravb_ring_init(struct net_device

*ndev, int q)

 static void ravb_emac_init_gbeth(struct net_device *ndev)  {
-	/* Place holder */
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	/* Receive frame limit set register */
+	ravb_write(ndev, GBETH_RX_BUFF_MAX + ETH_FCS_LEN, RFLR);
+
+	/* PAUSE prohibition */

    Should be:

	/* EMAC Mode: PAUSE prohibition; Duplex; TX; RX */

quoted

+	ravb_write(ndev, ECMR_ZPF | ((priv->duplex > 0) ? ECMR_DM : 0) |
+			 ECMR_TE | ECMR_RE | ECMR_RCPT |
+			 ECMR_TXF | ECMR_RXF | ECMR_PRM, ECMR);
+
+	ravb_set_rate_gbeth(ndev);
+
+	/* Set MAC address */
+	ravb_write(ndev,
+		   (ndev->dev_addr[0] << 24) | (ndev->dev_addr[1] << 16) |
+		   (ndev->dev_addr[2] << 8)  | (ndev->dev_addr[3]), MAHR);
+	ravb_write(ndev, (ndev->dev_addr[4] << 8)  | (ndev->dev_addr[5]),
+MALR);
+
+	/* E-MAC status register clear */
+	ravb_write(ndev, ECSR_ICD | ECSR_LCHNG | ECSR_PFRI, ECSR);
+
+	/* E-MAC interrupt enable register */
+	ravb_write(ndev, ECSIPR_ICDIP, ECSIPR);

   Too much repetitive code, I think...

Can you please clarify what are the codes repetitive here?

quoted

+
+	ravb_modify(ndev, CXR31, CXR31_SEL_LINK1, 0);
+	ravb_modify(ndev, CXR31, CXR31_SEL_LINK0, CXR31_SEL_LINK0);

   Can't be done in a single RMW?

Will do.

[...]

MBR, Sergey