Re: [PATCH 10/11] net: macb: Add support for RP1's MACB variant

From: Florian Fainelli
Date: Wed Aug 21 2024 - 13:01:44 EST


On 8/20/24 07:36, Andrea della Porta wrote:
RaspberryPi RP1 contains Cadence's MACB core. Implement the
changes to be able to operate the customization in the RP1.

Signed-off-by: Andrea della Porta <andrea.porta@xxxxxxxx>

You are doing a lot of things, all at once, and you should consider extracting your change into a smaller subset with bug fixes first:

- one commit which writes to the RBQPH the upper 32-bits of the RX ring DMA address, that looks like a bug fix

- one commit which retriggers a buffer read, even though that appears to be RP1 specific maybe, if not, then this is also a bug fix

- one commit that adds support for macb_shutdown() to kill DMA operations

- one commit which adds support for a configurable PHY reset line + delay specified in milli seconds

- one commit which adds support for controling the interrupt coalescing settings

And then you can add all of the RP1 specific bits like the AXI bridge configuration.

[snip]

@@ -1228,6 +1246,7 @@ struct macb_queue {
dma_addr_t tx_ring_dma;
struct work_struct tx_error_task;
bool txubr_pending;
+ bool tx_pending;
struct napi_struct napi_tx;
dma_addr_t rx_ring_dma;
@@ -1293,9 +1312,15 @@ struct macb {
u32 caps;
unsigned int dma_burst_length;
+ u8 aw2w_max_pipe;
+ u8 ar2r_max_pipe;
+ bool use_aw2b_fill;
phy_interface_t phy_interface;
+ struct gpio_desc *phy_reset_gpio;
+ int phy_reset_ms;

The delay cannot be negative, so this needs to be unsigned int.

+
/* AT91RM9200 transmit queue (1 on wire + 1 queued) */
struct macb_tx_skb rm9200_txq[2];
unsigned int max_tx_length;
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 11665be3a22c..5eb5be6c96fc 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -41,6 +41,9 @@
#include <linux/inetdevice.h>
#include "macb.h"
+static unsigned int txdelay = 35;
+module_param(txdelay, uint, 0644);
+
/* This structure is only used for MACB on SiFive FU540 devices */
struct sifive_fu540_macb_mgmt {
void __iomem *reg;
@@ -334,7 +337,7 @@ static int macb_mdio_wait_for_idle(struct macb *bp)
u32 val;
return readx_poll_timeout(MACB_READ_NSR, bp, val, val & MACB_BIT(IDLE),
- 1, MACB_MDIO_TIMEOUT);
+ 100, MACB_MDIO_TIMEOUT);

Why do we need to increase how frequently we poll?
--
Florian