On 8/3/21 8:57 AM, Biju Das wrote:

quoted

Subject: Re: [PATCH net-next v2 1/8] ravb: Add struct ravb_hw_info to
driver data

On 8/2/21 1:26 PM, Biju Das wrote:

quoted

The DMAC and EMAC blocks of Gigabit Ethernet IP found on RZ/G2L SoC
are similar to the R-Car Ethernet AVB IP. With a few changes in the
driver we can support both IPs.

Currently a runtime decision based on the chip type is used to
distinguish the HW differences between the SoC families.

The number of TX descriptors for R-Car Gen3 is 1 whereas on R-Car Gen2
and RZ/G2L it is 2. For cases like this it is better to select the
number of TX descriptors by using a structure with a value, rather
than a runtime decision based on the chip type.

This patch adds the num_tx_desc variable to struct ravb_hw_info and
also replaces the driver data chip type with struct ravb_hw_info by
moving chip type to it.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v2:
 * Incorporated Andrew and Sergei's review comments for making it

smaller patch

quoted

   and provided detailed description.
---
 drivers/net/ethernet/renesas/ravb.h      |  7 +++++
 drivers/net/ethernet/renesas/ravb_main.c | 38
+++++++++++++++---------
 2 files changed, 31 insertions(+), 14 deletions(-)

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

b/drivers/net/ethernet/renesas/ravb.h
index 80e62ca2e3d3..cfb972c05b34 100644

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

@@ -988,6 +988,11 @@ enum ravb_chip_id {
 	RCAR_GEN3,
 };

+struct ravb_hw_info {
+	enum ravb_chip_id chip_id;
+	int num_tx_desc;

   How about leaving that field in the *struct* ravb_private? And adding the following instead:

	unsigned unaligned_tx: 1;

quoted

   I think this is rather the driver's choice, than the h/w feature...
Perhaps a rename would help with that? :-)

It is consistent with current naming convention used by the driver. NUM_TX_DESC macro is replaced by num_tx_desc and  the below run time decision based on chip type for H/W configuration for Gen2/Gen3 is replaced by info->num_tx_desc.

priv->num_tx_desc = chip_id == RCAR_GEN2 ? NUM_TX_DESC_GEN2 : NUM_TX_DESC_GEN3;

   .. and then:

	priv->num_tx_desc =  info->unaligned_tx ? NUM_TX_DESC_GEN2 : NUM_TX_DESC_GEN3;

Please let me know, if I am missing anything,

Previously there is a suggestion to change the generic struct ravb_driver_data (which holds driver differences and HW features) with struct ravb_hw_info.

    Well, my plan was to place all the hardware features supported into the *struct* ravb_hw_info and leave all
the driver's software data in the *struct* ravb_private.

Regards,
Biju

[...]

MBR, Sergei