[PATCH net 1/1] net: stmmac: fix issue where clk is being unprepared twice

From: Wong Vee Khee
Date: Tue Jun 01 2021 - 22:26:54 EST

In the case of MDIO bus registration failure due to no external PHY
devices is connected to the MAC, clk_disable_unprepare() is called in
stmmac_bus_clk_config() and intel_eth_pci_probe() respectively.

The second call in intel_eth_pci_probe() will caused the following:-

[ 16.578605] intel-eth-pci 0000:00:1e.5: No PHY found
[ 16.583778] intel-eth-pci 0000:00:1e.5: stmmac_dvr_probe: MDIO bus (id: 2) registration failed
[ 16.680181] ------------[ cut here ]------------
[ 16.684861] stmmac-0000:00:1e.5 already disabled
[ 16.689547] WARNING: CPU: 13 PID: 2053 at drivers/clk/clk.c:952 clk_core_disable+0x96/0x1b0
[ 16.697963] Modules linked in: dwc3 iTCO_wdt mei_hdcp iTCO_vendor_support udc_core x86_pkg_temp_thermal kvm_intel marvell10g kvm sch_fq_codel nfsd irqbypass dwmac_intel(+) stmmac uio ax88179_178a pcs_xpcs phylink uhid spi_pxa2xx_platform usbnet mei_me pcspkr tpm_crb mii i2c_i801 dw_dmac dwc3_pci thermal dw_dmac_core intel_rapl_msr libphy i2c_smbus mei tpm_tis intel_th_gth tpm_tis_core tpm intel_th_acpi intel_pmc_core intel_th i915 fuse configfs snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hda_core snd_pcm snd_timer snd soundcore
[ 16.746785] CPU: 13 PID: 2053 Comm: systemd-udevd Tainted: G U 5.13.0-rc3-intel-lts #76
[ 16.756134] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-S ADP-S DRR4 CRB, BIOS ADLIFSI1.R00.1494.B00.2012031421 12/03/2020
[ 16.769465] RIP: 0010:clk_core_disable+0x96/0x1b0
[ 16.774222] Code: 00 8b 05 45 96 17 01 85 c0 7f 24 48 8b 5b 30 48 85 db 74 a5 8b 43 7c 85 c0 75 93 48 8b 33 48 c7 c7 6e 32 cc b7 e8 b2 5d 52 00 <0f> 0b 5b 5d c3 65 8b 05 76 31 18 49 89 c0 48 0f a3 05 bc 92 1a 01
[ 16.793016] RSP: 0018:ffffa44580523aa0 EFLAGS: 00010086
[ 16.798287] RAX: 0000000000000000 RBX: ffff8d7d0eb70a00 RCX: 0000000000000000
[ 16.805435] RDX: 0000000000000002 RSI: ffffffffb7c62d5f RDI: 00000000ffffffff
[ 16.812610] RBP: 0000000000000287 R08: 0000000000000000 R09: ffffa445805238d0
[ 16.819759] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8d7d0eb70a00
[ 16.826904] R13: ffff8d7d027370c8 R14: 0000000000000006 R15: ffffa44580523ad0
[ 16.834047] FS: 00007f9882fa2600(0000) GS:ffff8d80a0940000(0000) knlGS:0000000000000000
[ 16.842177] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 16.847966] CR2: 00007f9882bea3d8 CR3: 000000010b126001 CR4: 0000000000370ee0
[ 16.855144] Call Trace:
[ 16.857614] clk_core_disable_lock+0x1b/0x30
[ 16.861941] intel_eth_pci_probe.cold+0x11d/0x136 [dwmac_intel]
[ 16.867913] pci_device_probe+0xcf/0x150
[ 16.871890] really_probe+0xf5/0x3e0
[ 16.875526] driver_probe_device+0x64/0x150
[ 16.879763] device_driver_attach+0x53/0x60
[ 16.883998] __driver_attach+0x9f/0x150
[ 16.887883] ? device_driver_attach+0x60/0x60
[ 16.892288] ? device_driver_attach+0x60/0x60
[ 16.896698] bus_for_each_dev+0x77/0xc0
[ 16.900583] bus_add_driver+0x184/0x1f0
[ 16.904469] driver_register+0x6c/0xc0
[ 16.908268] ? 0xffffffffc07ae000
[ 16.911598] do_one_initcall+0x4a/0x210
[ 16.915489] ? kmem_cache_alloc_trace+0x305/0x4e0
[ 16.920247] do_init_module+0x5c/0x230
[ 16.924057] load_module+0x2894/0x2b70
[ 16.927857] ? __do_sys_finit_module+0xb5/0x120
[ 16.932441] __do_sys_finit_module+0xb5/0x120
[ 16.936845] do_syscall_64+0x42/0x80
[ 16.940476] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 16.945586] RIP: 0033:0x7f98830e5ccd
[ 16.949177] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 31 0c 00 f7 d8 64 89 01 48
[ 16.967970] RSP: 002b:00007ffc66b60168 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 16.975583] RAX: ffffffffffffffda RBX: 000055885de35ef0 RCX: 00007f98830e5ccd
[ 16.982725] RDX: 0000000000000000 RSI: 00007f98832541e3 RDI: 0000000000000012
[ 16.989868] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000000
[ 16.997042] R10: 0000000000000012 R11: 0000000000000246 R12: 00007f98832541e3
[ 17.004222] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc66b60328
[ 17.011369] ---[ end trace df06a3dab26b988c ]---
[ 17.016062] ------------[ cut here ]------------
[ 17.020701] stmmac-0000:00:1e.5 already unprepared

Removing the stmmac_bus_clks_config() call in stmmac_dvr_probe and let
dwmac-intel to handle the unprepare and disable of the clk device.

Fixes: 5ec55823438e ("net: stmmac: add clocks management for gmac driver")
Cc: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Signed-off-by: Wong Vee Khee <vee.khee.wong@xxxxxxxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 13720bf6f6ff..7437307326b2 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7046,7 +7046,6 @@ int stmmac_dvr_probe(struct device *device,
stmmac_napi_del(ndev);
error_hw_init:
destroy_workqueue(priv->wq);
- stmmac_bus_clks_config(priv, false);
bitmap_free(priv->af_xdp_zc_qps);

return ret;
--
2.25.1