Commit f5d5c17b authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'net-phy-fixed_phy-replace-list-of-fixed-phys-with-static-array' 

Heiner Kallweit says:

====================
net: phy: fixed_phy: replace list of fixed PHYs with static array

Due to max 32 PHY addresses being available per mii bus, using a list
can't support more fixed PHY's. And there's no known use case for as
much as 32 fixed PHY's on a system. 8 should be plenty of fixed PHY's,
so use an array of that size instead of a list. This allows to
significantly reduce the code size and complexity.
In addition replace heavy-weight IDA with a simple bitmap.
====================

Link: https://patch.msgid.link/110f676d-727c-4575-abe4-e383f98fc38f@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 8619e429 ca8934f8

drivers/net/phy/fixed_phy.c

+29 −54
Original line number Diff line number Diff line
@@ -10,39 +10,34 @@ 


#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/list.h>

#include <linux/mii.h>

#include <linux/phy.h>

#include <linux/phy_fixed.h>

#include <linux/err.h>

#include <linux/slab.h>

#include <linux/of.h>

#include <linux/idr.h>

#include <linux/netdevice.h>



#include "swphy.h"



/* The DSA loop driver may allocate 4 fixed PHY's, and 4 additional

 * fixed PHY's for a system should be sufficient.

 */

#define NUM_FP	8



struct fixed_phy {

	int addr;

	struct phy_device *phydev;

	struct fixed_phy_status status;

	int (*link_update)(struct net_device *, struct fixed_phy_status *);

	struct list_head node;

};



static DECLARE_BITMAP(fixed_phy_ids, NUM_FP);

static struct fixed_phy fmb_fixed_phys[NUM_FP];

static struct mii_bus *fmb_mii_bus;

static LIST_HEAD(fmb_phys);



static struct fixed_phy *fixed_phy_find(int addr)

{

	struct fixed_phy *fp;



	list_for_each_entry(fp, &fmb_phys, node) {

		if (fp->addr == addr)

			return fp;

	}



	return NULL;

	return test_bit(addr, fixed_phy_ids) ? fmb_fixed_phys + addr : NULL;

}



int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier)
@@ -108,42 +103,29 @@ int fixed_phy_set_link_update(struct phy_device *phydev, 
}

EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);



static int __fixed_phy_add(int phy_addr,

			   const struct fixed_phy_status *status)

static void fixed_phy_del(int phy_addr)

{

	struct fixed_phy *fp;

	int ret;



	ret = swphy_validate_state(status);

	if (ret < 0)

		return ret;



	fp = kzalloc(sizeof(*fp), GFP_KERNEL);

	fp = fixed_phy_find(phy_addr);

	if (!fp)

		return -ENOMEM;



	fp->addr = phy_addr;

	fp->status = *status;

	fp->status.link = true;



	list_add_tail(&fp->node, &fmb_phys);

		return;



	return 0;

	memset(fp, 0, sizeof(*fp));

	clear_bit(phy_addr, fixed_phy_ids);

}



static DEFINE_IDA(phy_fixed_ida);



static void fixed_phy_del(int phy_addr)

static int fixed_phy_get_free_addr(void)

{

	struct fixed_phy *fp;

	int addr;



	fp = fixed_phy_find(phy_addr);

	if (!fp)

		return;

	do {

		addr = find_first_zero_bit(fixed_phy_ids, NUM_FP);

		if (addr == NUM_FP)

			return -ENOSPC;

	} while (test_and_set_bit(addr, fixed_phy_ids));



	list_del(&fp->node);

	kfree(fp);

	ida_free(&phy_fixed_ida, phy_addr);

	return addr;

}



struct phy_device *fixed_phy_register(const struct fixed_phy_status *status,
@@ -153,19 +135,20 @@ struct phy_device *fixed_phy_register(const struct fixed_phy_status *status, 
	int phy_addr;

	int ret;



	ret = swphy_validate_state(status);

	if (ret < 0)

		return ERR_PTR(ret);



	if (!fmb_mii_bus || fmb_mii_bus->state != MDIOBUS_REGISTERED)

		return ERR_PTR(-EPROBE_DEFER);



	/* Get the next available PHY address, up to PHY_MAX_ADDR */

	phy_addr = ida_alloc_max(&phy_fixed_ida, PHY_MAX_ADDR - 1, GFP_KERNEL);

	/* Get the next available PHY address, up to NUM_FP */

	phy_addr = fixed_phy_get_free_addr();

	if (phy_addr < 0)

		return ERR_PTR(phy_addr);



	ret = __fixed_phy_add(phy_addr, status);

	if (ret < 0) {

		ida_free(&phy_fixed_ida, phy_addr);

		return ERR_PTR(ret);

	}

	fmb_fixed_phys[phy_addr].status = *status;

	fmb_fixed_phys[phy_addr].status.link = true;



	phy = get_phy_device(fmb_mii_bus, phy_addr, false);

	if (IS_ERR(phy)) {
@@ -237,16 +220,8 @@ module_init(fixed_mdio_bus_init); 


static void __exit fixed_mdio_bus_exit(void)

{

	struct fixed_phy *fp, *tmp;



	mdiobus_unregister(fmb_mii_bus);

	mdiobus_free(fmb_mii_bus);



	list_for_each_entry_safe(fp, tmp, &fmb_phys, node) {

		list_del(&fp->node);

		kfree(fp);

	}

	ida_destroy(&phy_fixed_ida);

}

module_exit(fixed_mdio_bus_exit);