From 902a66e08ceaadb9a7a1ab3a4f3af611cd1d8cba Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Sun, 8 Nov 2020 12:12:24 -0500 Subject: lan743x: correctly handle chips with internal PHY Commit 6f197fb63850 ("lan743x: Added fixed link and RGMII support") assumes that chips with an internal PHY will never have a devicetree entry. This is incorrect: even for these chips, a devicetree entry can be useful e.g. to pass the mac address from bootloader to chip: &pcie { status = "okay"; host@0 { reg = <0 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; lan7430: ethernet@0 { /* LAN7430 with internal PHY */ compatible = "microchip,lan743x"; status = "okay"; reg = <0 0 0 0 0>; /* filled in by bootloader */ local-mac-address = [00 00 00 00 00 00]; }; }; }; If a devicetree entry is present, the driver will not attach the chip to its internal phy, and the chip will be non-operational. Fix by tweaking the phy connection algorithm: - first try to connect to a phy specified in the devicetree (could be 'real' phy, or just a 'fixed-link') - if that doesn't succeed, try to connect to an internal phy, even if the chip has a devnode Tested on a LAN7430 with internal PHY. I cannot test a device using fixed-link, as I do not have access to one. Fixes: 6f197fb63850 ("lan743x: Added fixed link and RGMII support") Tested-by: Sven Van Asbroeck # lan7430 Reviewed-by: Andrew Lunn Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201108171224.23829-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers/net/ethernet/microchip/lan743x_main.c') diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index a1938842f828..bd77877cf1cc 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -1026,9 +1026,9 @@ static int lan743x_phy_open(struct lan743x_adapter *adapter) netdev = adapter->netdev; phynode = of_node_get(adapter->pdev->dev.of_node); - adapter->phy_mode = PHY_INTERFACE_MODE_GMII; if (phynode) { + /* try devicetree phy, or fixed link */ of_get_phy_mode(phynode, &adapter->phy_mode); if (of_phy_is_fixed_link(phynode)) { @@ -1044,13 +1044,15 @@ static int lan743x_phy_open(struct lan743x_adapter *adapter) lan743x_phy_link_status_change, 0, adapter->phy_mode); of_node_put(phynode); - if (!phydev) - goto return_error; - } else { + } + + if (!phydev) { + /* try internal phy */ phydev = phy_find_first(adapter->mdiobus); if (!phydev) goto return_error; + adapter->phy_mode = PHY_INTERFACE_MODE_GMII; ret = phy_connect_direct(netdev, phydev, lan743x_phy_link_status_change, adapter->phy_mode); -- cgit From 2b52a4b65bc8f14520fe6e996ea7fb3f7e400761 Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Mon, 9 Nov 2020 15:38:28 -0500 Subject: lan743x: fix "BUG: invalid wait context" when setting rx mode In the net core, the struct net_device_ops -> ndo_set_rx_mode() callback is called with the dev->addr_list_lock spinlock held. However, this driver's ndo_set_rx_mode callback eventually calls lan743x_dp_write(), which acquires a mutex. Mutex acquisition may sleep, and this is not allowed when holding a spinlock. Fix by removing the dp_lock mutex entirely. Its purpose is to prevent concurrent accesses to the data port. No concurrent accesses are possible, because the dev->addr_list_lock spinlock in the core only lets through one thread at a time. Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201109203828.5115-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 12 +++--------- drivers/net/ethernet/microchip/lan743x_main.h | 3 --- 2 files changed, 3 insertions(+), 12 deletions(-) (limited to 'drivers/net/ethernet/microchip/lan743x_main.c') diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index bd77877cf1cc..173158656559 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -674,14 +674,12 @@ clean_up: static int lan743x_dp_write(struct lan743x_adapter *adapter, u32 select, u32 addr, u32 length, u32 *buf) { - int ret = -EIO; u32 dp_sel; int i; - mutex_lock(&adapter->dp_lock); if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_, 1, 40, 100, 100)) - goto unlock; + return -EIO; dp_sel = lan743x_csr_read(adapter, DP_SEL); dp_sel &= ~DP_SEL_MASK_; dp_sel |= select; @@ -693,13 +691,10 @@ static int lan743x_dp_write(struct lan743x_adapter *adapter, lan743x_csr_write(adapter, DP_CMD, DP_CMD_WRITE_); if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_, 1, 40, 100, 100)) - goto unlock; + return -EIO; } - ret = 0; -unlock: - mutex_unlock(&adapter->dp_lock); - return ret; + return 0; } static u32 lan743x_mac_mii_access(u16 id, u16 index, int read) @@ -2735,7 +2730,6 @@ static int lan743x_hardware_init(struct lan743x_adapter *adapter, adapter->intr.irq = adapter->pdev->irq; lan743x_csr_write(adapter, INT_EN_CLR, 0xFFFFFFFF); - mutex_init(&adapter->dp_lock); ret = lan743x_gpio_init(adapter); if (ret) diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h index c61a40411317..a536f4a4994d 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.h +++ b/drivers/net/ethernet/microchip/lan743x_main.h @@ -712,9 +712,6 @@ struct lan743x_adapter { struct lan743x_csr csr; struct lan743x_intr intr; - /* lock, used to prevent concurrent access to data port */ - struct mutex dp_lock; - struct lan743x_gpio gpio; struct lan743x_ptp ptp; -- cgit From edbc21113bde13ca3d06eec24b621b1f628583dd Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Thu, 12 Nov 2020 10:25:13 -0500 Subject: lan743x: fix use of uninitialized variable When no devicetree is present, the driver will use an uninitialized variable. Fix by initializing this variable. Fixes: 902a66e08cea ("lan743x: correctly handle chips with internal PHY") Reported-by: kernel test robot Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201112152513.1941-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ethernet/microchip/lan743x_main.c') diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index 173158656559..e2c99d909247 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -1014,8 +1014,8 @@ static void lan743x_phy_close(struct lan743x_adapter *adapter) static int lan743x_phy_open(struct lan743x_adapter *adapter) { struct lan743x_phy *phy = &adapter->phy; + struct phy_device *phydev = NULL; struct device_node *phynode; - struct phy_device *phydev; struct net_device *netdev; int ret = -EIO; -- cgit From e35df62e04cc6fc4b9d90d054732f138349ff9b1 Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Thu, 12 Nov 2020 13:59:49 -0500 Subject: lan743x: fix issue causing intermittent kernel log warnings When running this chip on arm imx6, we intermittently observe the following kernel warning in the log, especially when the system is under high load: [ 50.119484] ------------[ cut here ]------------ [ 50.124377] WARNING: CPU: 0 PID: 303 at kernel/softirq.c:169 __local_bh_enable_ip+0x100/0x184 [ 50.132925] IRQs not enabled as expected [ 50.159250] CPU: 0 PID: 303 Comm: rngd Not tainted 5.7.8 #1 [ 50.164837] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [ 50.171395] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 50.179162] [] (show_stack) from [] (dump_stack+0xac/0xd8) [ 50.186408] [] (dump_stack) from [] (__warn+0xd0/0x10c) [ 50.193391] [] (__warn) from [] (warn_slowpath_fmt+0x98/0xc4) [ 50.200892] [] (warn_slowpath_fmt) from [] (__local_bh_enable_ip+0x100/0x184) [ 50.209860] [] (__local_bh_enable_ip) from [] (destroy_conntrack+0x48/0xd8 [nf_conntrack]) [ 50.220038] [] (destroy_conntrack [nf_conntrack]) from [] (nf_conntrack_destroy+0x94/0x168) [ 50.230160] [] (nf_conntrack_destroy) from [] (skb_release_head_state+0xa0/0xd0) [ 50.239314] [] (skb_release_head_state) from [] (skb_release_all+0xc/0x24) [ 50.247946] [] (skb_release_all) from [] (consume_skb+0x74/0x17c) [ 50.255796] [] (consume_skb) from [] (lan743x_tx_release_desc+0x120/0x124) [ 50.264428] [] (lan743x_tx_release_desc) from [] (lan743x_tx_napi_poll+0x5c/0x18c) [ 50.273755] [] (lan743x_tx_napi_poll) from [] (net_rx_action+0x118/0x4a4) [ 50.282306] [] (net_rx_action) from [] (__do_softirq+0x13c/0x53c) [ 50.290157] [] (__do_softirq) from [] (irq_exit+0x150/0x17c) [ 50.297575] [] (irq_exit) from [] (__handle_domain_irq+0x60/0xb0) [ 50.305423] [] (__handle_domain_irq) from [] (gic_handle_irq+0x4c/0x90) [ 50.313790] [] (gic_handle_irq) from [] (__irq_usr+0x54/0x80) [ 50.321287] Exception stack(0xecd99fb0 to 0xecd99ff8) [ 50.326355] 9fa0: 1cf1aa74 00000001 00000001 00000000 [ 50.334547] 9fc0: 00000001 00000000 00000000 00000000 00000000 00000000 00004097 b6d17d14 [ 50.342738] 9fe0: 00000001 b6d17c60 00000000 b6e71f94 800b0010 ffffffff [ 50.349364] irq event stamp: 2525027 [ 50.352955] hardirqs last enabled at (2525026): [] net_rx_action+0xb4/0x4a4 [ 50.360892] hardirqs last disabled at (2525027): [] _raw_spin_lock_irqsave+0x1c/0x50 [ 50.369517] softirqs last enabled at (2524660): [] __do_softirq+0x38c/0x53c [ 50.377446] softirqs last disabled at (2524693): [] irq_exit+0x150/0x17c [ 50.385027] ---[ end trace c0b571db4bc8087d ]--- The driver is calling dev_kfree_skb() from code inside a spinlock, where h/w interrupts are disabled. This is forbidden, as documented in include/linux/netdevice.h. The correct function to use dev_kfree_skb_irq(), or dev_kfree_skb_any(). Fix by using the correct dev_kfree_skb_xxx() functions: in lan743x_tx_release_desc(): called by lan743x_tx_release_completed_descriptors() called by in lan743x_tx_napi_poll() which holds a spinlock called by lan743x_tx_release_all_descriptors() called by lan743x_tx_close() which can-sleep conclusion: use dev_kfree_skb_any() in lan743x_tx_xmit_frame(): which holds a spinlock conclusion: use dev_kfree_skb_irq() in lan743x_tx_close(): which can-sleep conclusion: use dev_kfree_skb() in lan743x_rx_release_ring_element(): called by lan743x_rx_close() which can-sleep called by lan743x_rx_open() which can-sleep conclusion: use dev_kfree_skb() Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201112185949.11315-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/net/ethernet/microchip/lan743x_main.c') diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index e2c99d909247..18c053b860ab 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -1307,13 +1307,13 @@ clean_up_data_descriptor: goto clear_active; if (!(buffer_info->flags & TX_BUFFER_INFO_FLAG_TIMESTAMP_REQUESTED)) { - dev_kfree_skb(buffer_info->skb); + dev_kfree_skb_any(buffer_info->skb); goto clear_skb; } if (cleanup) { lan743x_ptp_unrequest_tx_timestamp(tx->adapter); - dev_kfree_skb(buffer_info->skb); + dev_kfree_skb_any(buffer_info->skb); } else { ignore_sync = (buffer_info->flags & TX_BUFFER_INFO_FLAG_IGNORE_SYNC) != 0; @@ -1623,7 +1623,7 @@ static netdev_tx_t lan743x_tx_xmit_frame(struct lan743x_tx *tx, if (required_number_of_descriptors > lan743x_tx_get_avail_desc(tx)) { if (required_number_of_descriptors > (tx->ring_size - 1)) { - dev_kfree_skb(skb); + dev_kfree_skb_irq(skb); } else { /* save to overflow buffer */ tx->overflow_skb = skb; @@ -1656,7 +1656,7 @@ static netdev_tx_t lan743x_tx_xmit_frame(struct lan743x_tx *tx, start_frame_length, do_timestamp, skb->ip_summed == CHECKSUM_PARTIAL)) { - dev_kfree_skb(skb); + dev_kfree_skb_irq(skb); goto unlock; } @@ -1675,7 +1675,7 @@ static netdev_tx_t lan743x_tx_xmit_frame(struct lan743x_tx *tx, * frame assembler clean up was performed inside * lan743x_tx_frame_add_fragment */ - dev_kfree_skb(skb); + dev_kfree_skb_irq(skb); goto unlock; } } -- cgit From 796a2665ca3e91ebaba7222f76fd9a035714e2d8 Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Thu, 12 Nov 2020 15:47:41 -0500 Subject: lan743x: prevent entire kernel HANG on open, for some platforms On arm imx6, when opening the chip's netdev, the whole Linux kernel intermittently hangs/freezes. This is caused by a bug in the driver code which tests if pcie interrupts are working correctly, using the software interrupt: 1. open: enable the software interrupt 2. open: tell the chip to assert the software interrupt 3. open: wait for flag 4. ISR: acknowledge s/w interrupt, set flag 5. open: notice flag, disable the s/w interrupt, continue Unfortunately the ISR only acknowledges the s/w interrupt, but does not disable it. This will re-trigger the ISR in a tight loop. On some (lucky) platforms, open proceeds to disable the s/w interrupt even while the ISR is 'spinning'. On arm imx6, the spinning ISR does not allow open to proceed, resulting in a hung Linux kernel. Fix minimally by disabling the s/w interrupt in the ISR, which will prevent it from spinning. This won't break anything because the s/w interrupt is used as a one-shot interrupt. Note that this is a minimal fix, overlooking many possible cleanups, e.g.: - lan743x_intr_software_isr() is completely redundant and reads INT_STS twice for no apparent reason - disabling the s/w interrupt in lan743x_intr_test_isr() is now redundant, but harmless - waiting on software_isr_flag can be converted from a sleeping poll loop to wait_event_timeout() Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Tested-by: Sven Van Asbroeck # arm imx6 lan7430 Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201112204741.12375-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/net/ethernet/microchip/lan743x_main.c') diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index 18c053b860ab..b319c22c211c 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -148,7 +148,8 @@ static void lan743x_intr_software_isr(void *context) int_sts = lan743x_csr_read(adapter, INT_STS); if (int_sts & INT_BIT_SW_GP_) { - lan743x_csr_write(adapter, INT_STS, INT_BIT_SW_GP_); + /* disable the interrupt to prevent repeated re-triggering */ + lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_SW_GP_); intr->software_isr_flag = 1; } } -- cgit