[PATCHv2 net-next 06/18] net: ibm: emac: remove bootlist support

From: Rosen Penev
Date: Tue Oct 01 2024 - 17:00:27 EST


This seems to be mainly used for deterministic interfaces. systemd
already does this in userspace.

Allows simplifying the driver with a single module_platform_driver.

Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
drivers/net/ethernet/ibm/emac/core.c | 117 +++------------------------
1 file changed, 9 insertions(+), 108 deletions(-)

diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c
index a55e84eb1d4d..a4701e2f9f73 100644
--- a/drivers/net/ethernet/ibm/emac/core.c
+++ b/drivers/net/ethernet/ibm/emac/core.c
@@ -95,21 +95,6 @@ MODULE_LICENSE("GPL");
static u32 busy_phy_map;
static DEFINE_MUTEX(emac_phy_map_lock);

-/* Having stable interface names is a doomed idea. However, it would be nice
- * if we didn't have completely random interface names at boot too :-) It's
- * just a matter of making everybody's life easier. Since we are doing
- * threaded probing, it's a bit harder though. The base idea here is that
- * we make up a list of all emacs in the device-tree before we register the
- * driver. Every emac will then wait for the previous one in the list to
- * initialize before itself. We should also keep that list ordered by
- * cell_index.
- * That list is only 4 entries long, meaning that additional EMACs don't
- * get ordering guarantees unless EMAC_BOOT_LIST_SIZE is increased.
- */
-
-#define EMAC_BOOT_LIST_SIZE 4
-static struct device_node *emac_boot_list[EMAC_BOOT_LIST_SIZE];
-
/* I don't want to litter system log with timeout errors
* when we have brain-damaged PHY.
*/
@@ -2330,14 +2315,12 @@ struct emac_depentry {
#define EMAC_DEP_RGMII_IDX 2
#define EMAC_DEP_TAH_IDX 3
#define EMAC_DEP_MDIO_IDX 4
-#define EMAC_DEP_PREV_IDX 5
-#define EMAC_DEP_COUNT 6
+#define EMAC_DEP_COUNT 5

static int emac_check_deps(struct emac_instance *dev,
struct emac_depentry *deps)
{
int i, there = 0;
- struct device_node *np;

for (i = 0; i < EMAC_DEP_COUNT; i++) {
/* no dependency on that item, allright */
@@ -2345,17 +2328,6 @@ static int emac_check_deps(struct emac_instance *dev,
there++;
continue;
}
- /* special case for blist as the dependency might go away */
- if (i == EMAC_DEP_PREV_IDX) {
- np = *(dev->blist - 1);
- if (np == NULL) {
- deps[i].phandle = 0;
- there++;
- continue;
- }
- if (deps[i].node == NULL)
- deps[i].node = of_node_get(np);
- }
if (deps[i].node == NULL)
deps[i].node = of_find_node_by_phandle(deps[i].phandle);
if (deps[i].node == NULL)
@@ -2397,8 +2369,6 @@ static int emac_wait_deps(struct emac_instance *dev)
deps[EMAC_DEP_TAH_IDX].phandle = dev->tah_ph;
if (dev->mdio_ph)
deps[EMAC_DEP_MDIO_IDX].phandle = dev->mdio_ph;
- if (dev->blist && dev->blist > emac_boot_list)
- deps[EMAC_DEP_PREV_IDX].phandle = 0xffffffffu;
err = emac_check_deps(dev, deps);
for (i = 0; i < EMAC_DEP_COUNT; i++) {
of_node_put(deps[i].node);
@@ -2412,7 +2382,6 @@ static int emac_wait_deps(struct emac_instance *dev)
dev->tah_dev = deps[EMAC_DEP_TAH_IDX].ofdev;
dev->mdio_dev = deps[EMAC_DEP_MDIO_IDX].ofdev;
}
- platform_device_put(deps[EMAC_DEP_PREV_IDX].ofdev);
return err;
}

@@ -2993,8 +2962,7 @@ static int emac_probe(struct platform_device *ofdev)
struct net_device *ndev;
struct emac_instance *dev;
struct device_node *np = ofdev->dev.of_node;
- struct device_node **blist = NULL;
- int err, i;
+ int err;

/* Skip unused/unwired EMACS. We leave the check for an unused
* property here for now, but new flat device trees should set a
@@ -3003,21 +2971,14 @@ static int emac_probe(struct platform_device *ofdev)
if (of_property_read_bool(np, "unused") || !of_device_is_available(np))
return -ENODEV;

- /* Find ourselves in the bootlist if we are there */
- for (i = 0; i < EMAC_BOOT_LIST_SIZE; i++)
- if (emac_boot_list[i] == np)
- blist = &emac_boot_list[i];
-
/* Allocate our net_device structure */
- err = -ENOMEM;
ndev = devm_alloc_etherdev(&ofdev->dev, sizeof(struct emac_instance));
if (!ndev)
- goto err_gone;
+ return -ENOMEM;

dev = netdev_priv(ndev);
dev->ndev = ndev;
dev->ofdev = ofdev;
- dev->blist = blist;
SET_NETDEV_DEV(ndev, &ofdev->dev);

/* Initialize some embedded data structures */
@@ -3029,16 +2990,15 @@ static int emac_probe(struct platform_device *ofdev)
/* Init various config data based on device-tree */
err = emac_init_config(dev);
if (err)
- goto err_gone;
+ return err;

/* Setup error IRQ handler */
dev->emac_irq = platform_get_irq(ofdev, 0);
err = devm_request_irq(&ofdev->dev, dev->emac_irq, emac_irq, 0, "EMAC",
dev);
if (err) {
- dev_err_probe(&ofdev->dev, err, "failed to request IRQ %d",
- dev->emac_irq);
- goto err_gone;
+ return dev_err_probe(&ofdev->dev, err,
+ "failed to request IRQ %d", dev->emac_irq);
}

ndev->irq = dev->emac_irq;
@@ -3046,14 +3006,13 @@ static int emac_probe(struct platform_device *ofdev)
dev->emacp = devm_platform_ioremap_resource(ofdev, 0);
if (IS_ERR(dev->emacp)) {
dev_err(&ofdev->dev, "can't map device registers");
- err = PTR_ERR(dev->emacp);
- goto err_gone;
+ return PTR_ERR(dev->emacp);
}

/* Wait for dependent devices */
err = emac_wait_deps(dev);
if (err)
- goto err_gone;
+ return err;
dev->mal = platform_get_drvdata(dev->mal_dev);
if (dev->mdio_dev != NULL)
dev->mdio_instance = platform_get_drvdata(dev->mdio_dev);
@@ -3181,9 +3140,6 @@ static int emac_probe(struct platform_device *ofdev)
mal_unregister_commac(dev->mal, &dev->commac);
err_rel_deps:
emac_put_deps(dev);
- err_gone:
- if (blist)
- *blist = NULL;
return err;
}

@@ -3237,59 +3193,4 @@ static struct platform_driver emac_driver = {
.remove_new = emac_remove,
};

-static void __init emac_make_bootlist(void)
-{
- struct device_node *np = NULL;
- int j, max, i = 0;
- int cell_indices[EMAC_BOOT_LIST_SIZE];
-
- /* Collect EMACs */
- while((np = of_find_all_nodes(np)) != NULL) {
- u32 idx;
-
- if (of_match_node(emac_match, np) == NULL)
- continue;
- if (of_property_read_bool(np, "unused"))
- continue;
- if (of_property_read_u32(np, "cell-index", &idx))
- continue;
- cell_indices[i] = idx;
- emac_boot_list[i++] = of_node_get(np);
- if (i >= EMAC_BOOT_LIST_SIZE) {
- of_node_put(np);
- break;
- }
- }
- max = i;
-
- /* Bubble sort them (doh, what a creative algorithm :-) */
- for (i = 0; max > 1 && (i < (max - 1)); i++)
- for (j = i; j < max; j++) {
- if (cell_indices[i] > cell_indices[j]) {
- swap(emac_boot_list[i], emac_boot_list[j]);
- swap(cell_indices[i], cell_indices[j]);
- }
- }
-}
-
-static int __init emac_init(void)
-{
- /* Build EMAC boot list */
- emac_make_bootlist();
-
- return platform_driver_register(&emac_driver);
-}
-
-static void __exit emac_exit(void)
-{
- int i;
-
- platform_driver_unregister(&emac_driver);
-
- /* Destroy EMAC boot list */
- for (i = 0; i < EMAC_BOOT_LIST_SIZE; i++)
- of_node_put(emac_boot_list[i]);
-}
-
-module_init(emac_init);
-module_exit(emac_exit);
+module_platform_driver(emac_driver);
--
2.46.2