On 20.09.2021 18:11, Florian Fainelli wrote:
On 9/20/21 5:34 AM, Rafał Miłecki wrote:
From: Rafał Miłecki <rafal@xxxxxxxxxx>
Check ethernet controller DT node for "mdio" subnode and use it with
of_mdiobus_register() when present. That allows specifying MDIO and its
PHY devices in a standard DT based way.
This is required for BCM53573 SoC support which has an MDIO attached
switch.
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c b/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c
index 6ce80cbcb48e..086739e4f40a 100644
--- a/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c
+++ b/drivers/net/ethernet/broadcom/bgmac-bcma-mdio.c
@@ -10,6 +10,7 @@
#include <linux/bcma/bcma.h>
#include <linux/brcmphy.h>
+#include <linux/of_mdio.h>
#include "bgmac.h"
static bool bcma_mdio_wait_value(struct bcma_device *core, u16 reg, u32 mask,
@@ -211,6 +212,7 @@ struct mii_bus *bcma_mdio_mii_register(struct bgmac *bgmac)
{
struct bcma_device *core = bgmac->bcma.core;
struct mii_bus *mii_bus;
+ struct device_node *np;
int err;
mii_bus = mdiobus_alloc();
@@ -229,7 +231,9 @@ struct mii_bus *bcma_mdio_mii_register(struct bgmac *bgmac)
mii_bus->parent = &core->dev;
mii_bus->phy_mask = ~(1 << bgmac->phyaddr);
- err = mdiobus_register(mii_bus);
+ np = of_get_child_by_name(core->dev.of_node, "mdio");
I believe this leaks np and the use case is not exactly clear to me
here. AFAICT the Northstar SoCs have two MDIO controllers: one for
internal PHYs and one for external PHYs which how you would attach a
switch to the chip (in chipcommonA). Is 53573 somewhat different here?
What is the MDIO bus driver that is being used?
of_get_child_by_name() doesn't seem to increase refcount or anything and
I think it's how most drivers handle it. I don't think it should leak.
BCM53573 is a built with some older blocks. Please check:
4ebd50472899 ("ARM: BCM53573: Initial support for Broadcom BCM53573 SoCs")
BCM53573 series is a new family with embedded wireless. By marketing
people it's sometimes called Northstar but it uses different CPU and has
different architecture so we need a new symbol for it.
Fortunately it shares some peripherals with other iProc based SoCs so we
will be able to reuse some drivers/bindings.
e90d2d51c412 ("ARM: BCM5301X: Add basic dts for BCM53573 based Tenda AC9")
BCM53573 seems to be low priced alternative for Northstar chipsts. It
uses single core Cortex-A7 and doesn't have SDU or local (TWD) timer. It
was also stripped out of independent SPI controller and 2 GMACs.
Northstar uses SRAB which is some memory based (0x18007000) access to
switch register space.
BCM53573 uses different blocks & mappings and it doesn't include SRAB at
0x18007000. Accessing switch registers is handled over MDIO.
