ARM: imx6: disable deeper idle states when FEC is active w/o HW workaround
The i.MX6 Q/DL has an erratum (ERR006687) that prevents the FEC from
waking the CPUs when they are in wait(unclocked) state. As the hardware
workaround isn't applicable to all boards, disable the deeper idle state
when the workaround isn't present and the FEC is in use.
This allows to safely run a kernel with CPUidle enabled on all i.MX6
boards.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: David S. Miller <davem@davemloft.net> (for network changes)
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index f58f9ea..dc71a88 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -442,6 +442,8 @@
#define FEC_QUIRK_SINGLE_MDIO (1 << 11)
/* Controller supports RACC register */
#define FEC_QUIRK_HAS_RACC (1 << 12)
+/* Interrupt doesn't wake CPU from deep idle */
+#define FEC_QUIRK_ERR006687 (1 << 13)
struct bufdesc_prop {
int qid;
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index ca2cccc..8c2110b 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -60,6 +60,7 @@
#include <linux/if_vlan.h>
#include <linux/pinctrl/consumer.h>
#include <linux/prefetch.h>
+#include <soc/imx/cpuidle.h>
#include <asm/cacheflush.h>
@@ -2820,6 +2821,9 @@
if (ret)
goto err_enet_mii_probe;
+ if (fep->quirks & FEC_QUIRK_ERR006687)
+ imx6q_cpuidle_fec_irqs_used();
+
napi_enable(&fep->napi);
phy_start(ndev->phydev);
netif_tx_start_all_queues(ndev);
@@ -2855,6 +2859,9 @@
phy_disconnect(ndev->phydev);
+ if (fep->quirks & FEC_QUIRK_ERR006687)
+ imx6q_cpuidle_fec_irqs_unused();
+
fec_enet_clk_enable(ndev, false);
pinctrl_pm_select_sleep_state(&fep->pdev->dev);
pm_runtime_mark_last_busy(&fep->pdev->dev);
@@ -3294,6 +3301,11 @@
platform_set_drvdata(pdev, ndev);
+ if ((of_machine_is_compatible("fsl,imx6q") ||
+ of_machine_is_compatible("fsl,imx6dl")) &&
+ !of_property_read_bool(np, "fsl,err006687-workaround-present"))
+ fep->quirks |= FEC_QUIRK_ERR006687;
+
if (of_get_property(np, "fsl,magic-packet", NULL))
fep->wol_flag |= FEC_WOL_HAS_MAGIC_PACKET;