netdev - [PATCH net-next 09/10 v2] net: ethernet: ixp4xx: Get port ID from base address

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri,  1 Nov 2019 14:02:23 +0100
From:   Linus Walleij <linus.walleij@...aro.org>
To:     netdev@...r.kernel.org, "David S . Miller" <davem@...emloft.net>
Cc:     Arnd Bergmann <arnd@...db.de>,
        Jakub Kicinski <jakub.kicinski@...ronome.com>,
        Linus Walleij <linus.walleij@...aro.org>
Subject: [PATCH net-next 09/10 v2] net: ethernet: ixp4xx: Get port ID from base address

The port->id was picked from the platform device .id field,
but this is not supposed to be used for passing around
random numbers in hardware. Identify the port ID number
from the base address instead.

This is necessary for Device Tree conversion: to DT
these are just three networking engines (NPEs) that the OS
can choose to use however it likes. When we move to DT we
cannot get these port numbers from the device tree.

That they behave differently and that the driver has to cope
with that is due to different firmware being loaded into the
different NPE:s. DT doesn't care about that. The firmware
can theoretically be changed, but the DT bindings can not.

Signed-off-by: Linus Walleij <linus.walleij@...aro.org>
---
ChangeLog v1->v2:
- Rebased on the rest of the series.
---
 drivers/net/ethernet/xscale/ixp4xx_eth.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/xscale/ixp4xx_eth.c b/drivers/net/ethernet/xscale/ixp4xx_eth.c
index ee45215c4ba4..c5835a2fb965 100644
--- a/drivers/net/ethernet/xscale/ixp4xx_eth.c
+++ b/drivers/net/ethernet/xscale/ixp4xx_eth.c
@@ -1379,7 +1379,6 @@ static int ixp4xx_eth_probe(struct platform_device *pdev)
 	SET_NETDEV_DEV(ndev, dev);
 	port = netdev_priv(ndev);
 	port->netdev = ndev;
-	port->id = pdev->id;
 
 	/* Get the port resource and remap */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1388,13 +1387,15 @@ static int ixp4xx_eth_probe(struct platform_device *pdev)
 	regs_phys = res->start;
 	port->regs = devm_ioremap_resource(dev, res);
 
-	switch (port->id) {
-	case IXP4XX_ETH_NPEA:
+	switch (res->start) {
+	case 0xc800c000:
+		port->id = IXP4XX_ETH_NPEA;
 		/* If the MDIO bus is not up yet, defer probe */
 		if (!mdio_bus)
 			return -EPROBE_DEFER;
 		break;
-	case IXP4XX_ETH_NPEB:
+	case 0xc8009000:
+		port->id = IXP4XX_ETH_NPEB;
 		/*
 		 * On all except IXP43x, NPE-B is used for the MDIO bus.
 		 * If there is no NPE-B in the feature set, bail out, else
@@ -1411,7 +1412,8 @@ static int ixp4xx_eth_probe(struct platform_device *pdev)
 		if (!mdio_bus)
 			return -EPROBE_DEFER;
 		break;
-	case IXP4XX_ETH_NPEC:
+	case 0xc800a000:
+		port->id = IXP4XX_ETH_NPEC;
 		/*
 		 * IXP43x lacks NPE-B and uses NPE-C for the MDIO bus access,
 		 * of there is no NPE-C, no bus, nothing works, so bail out.
-- 
2.21.0