When a switch is attached to the mdio bus, the mdio bus can be used
while the interface is not open. If the IPG clock is not enabled, MDIO
reads/writes will simply time out. Add support for runtime PM to
control the clocks and other resources. Enable/disable the clocks
using runtime PM, with open()/close() and mdio read()/write() function
triggering runtime PM operations. Auto suspend is used, since there
are likely to be a number of MDIO operations in a burst during DSA
probe.
Signed-off-by: Andrew Lunn <and...@lunn.ch>
Cc: Duan Andy <fugang.d...@freescale.com>
---
RFC since net-next is closed for the merge window. Please send
comments, Acked-by, etc, and i will then resubmit once net-next
reopens.
drivers/net/ethernet/freescale/fec_main.c | 62 ++++++++++++++++++++++---------
1 file changed, 45 insertions(+), 17 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec_main.c
b/drivers/net/ethernet/freescale/fec_main.c
index bf4cf3fbb5f2..9b4d53132180 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -24,6 +24,7 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
+#include <linux/pm_runtime.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
@@ -77,6 +78,7 @@ static void fec_enet_itr_coal_init(struct net_device *ndev);
#define FEC_ENET_RAEM_V 0x8
#define FEC_ENET_RAFL_V 0x8
#define FEC_ENET_OPD_V 0xFFF0
+#define FEC_MDIO_PM_TIMEOUT 100 /* ms */
static struct platform_device_id fec_devtype[] = {
{
@@ -1763,11 +1765,15 @@ static void fec_enet_adjust_link(struct net_device
*ndev)
static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
struct fec_enet_private *fep = bus->priv;
+ struct device *dev = &fep->pdev->dev;
unsigned long time_left;
+ int ret = 0;
fep->mii_timeout = 0;
init_completion(&fep->mdio_done);
+ pm_runtime_get_sync(dev);
+
/* start a read op */
writel(FEC_MMFR_ST | FEC_MMFR_OP_READ |
FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(regnum) |
@@ -1779,22 +1785,32 @@ static int fec_enet_mdio_read(struct mii_bus *bus, int
mii_id, int regnum)
if (time_left == 0) {
fep->mii_timeout = 1;
netdev_err(fep->netdev, "MDIO read timeout\n");
- return -ETIMEDOUT;
+ ret = -ETIMEDOUT;
+ goto out;
}
- /* return value */
- return FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));
+ ret = FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));
+
+out:
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return ret;
}
static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
u16 value)
{
struct fec_enet_private *fep = bus->priv;
+ struct device *dev = &fep->pdev->dev;
unsigned long time_left;
+ int ret = 0;
fep->mii_timeout = 0;
init_completion(&fep->mdio_done);
+ pm_runtime_get_sync(dev);
+
/* start a write op */
writel(FEC_MMFR_ST | FEC_MMFR_OP_WRITE |
FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(regnum) |
@@ -1807,10 +1823,13 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int
mii_id, int regnum,
if (time_left == 0) {
fep->mii_timeout = 1;
netdev_err(fep->netdev, "MDIO write timeout\n");
- return -ETIMEDOUT;
+ ret = -ETIMEDOUT;
}
- return 0;
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return ret;
}
static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
@@ -2844,9 +2863,7 @@ fec_enet_open(struct net_device *ndev)
int ret;
pinctrl_pm_select_default_state(&fep->pdev->dev);
- ret = fec_enet_clk_enable(ndev, true);
- if (ret)
- return ret;
+ pm_runtime_get_sync(&fep->pdev->dev);
/* I should reset the ring buffers here, but I don't yet know
* a simple way to do that.
@@ -2874,7 +2891,8 @@ fec_enet_open(struct net_device *ndev)
err_enet_mii_probe:
fec_enet_free_buffers(ndev);
err_enet_alloc:
- fec_enet_clk_enable(ndev, false);
+ pm_runtime_mark_last_busy(&fep->pdev->dev);
+ pm_runtime_put_autosuspend(&fep->pdev->dev);
pinctrl_pm_select_sleep_state(&fep->pdev->dev);
return ret;
}
@@ -2895,8 +2913,10 @@ fec_enet_close(struct net_device *ndev)
phy_disconnect(fep->phy_dev);
fep->phy_dev = NULL;
- fec_enet_clk_enable(ndev, false);
pinctrl_pm_select_sleep_state(&fep->pdev->dev);
+ pm_runtime_mark_last_busy(&fep->pdev->dev);
+ pm_runtime_put_autosuspend(&fep->pdev->dev);
+
fec_enet_free_buffers(ndev);
return 0;
@@ -3426,8 +3446,9 @@ fec_probe(struct platform_device *pdev)
/* Carrier starts down, phylib will bring it up */
netif_carrier_off(ndev);
- fec_enet_clk_enable(ndev, false);
pinctrl_pm_select_sleep_state(&pdev->dev);
+ pm_runtime_set_active(&ndev->dev);
+ pm_runtime_enable(&ndev->dev);
ret = register_netdev(ndev);
if (ret)
@@ -3441,6 +3462,12 @@ fec_probe(struct platform_device *pdev)
fep->rx_copybreak = COPYBREAK_DEFAULT;
INIT_WORK(&fep->tx_timeout_work, fec_enet_timeout_work);
+
+ pm_runtime_set_autosuspend_delay(&ndev->dev, FEC_MDIO_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(&ndev->dev);
+ pm_runtime_mark_last_busy(&ndev->dev);
+ pm_runtime_put_autosuspend(&ndev->dev);
+
return 0;
failed_register:
@@ -3496,10 +3523,11 @@ static int __maybe_unused fec_suspend(struct device
*dev)
netif_device_detach(ndev);
netif_tx_unlock_bh(ndev);
fec_stop(ndev);
- fec_enet_clk_enable(ndev, false);
if (!(fep->wol_flag & FEC_WOL_FLAG_ENABLE))
pinctrl_pm_select_sleep_state(&fep->pdev->dev);
}
+
+ fec_enet_clk_enable(ndev, false);
rtnl_unlock();
if (fep->reg_phy && !(fep->wol_flag & FEC_WOL_FLAG_ENABLE))
@@ -3529,12 +3557,12 @@ static int __maybe_unused fec_resume(struct device *dev)
}
rtnl_lock();
+ ret = fec_enet_clk_enable(ndev, true);
+ if (ret) {
+ rtnl_unlock();
+ goto failed_clk;
+ }
if (netif_running(ndev)) {
- ret = fec_enet_clk_enable(ndev, true);
- if (ret) {
- rtnl_unlock();
- goto failed_clk;
- }
if (fep->wol_flag & FEC_WOL_FLAG_ENABLE) {
if (pdata && pdata->sleep_mode_enable)
pdata->sleep_mode_enable(false);
--
2.1.4
--
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