Sergio Paracuellos c7b65650c7 staging: mt7621-pci: avoid to re-disable clock for those pcies not in use ... Clock driver for this SoC is using some gates to properly enabling and disabling the access to peripherals. Those gates that are not in use are properly being automatically disabled by the kernel. Pcie driver is explicitly doing a 'clk_disable_unprepare' call for gates of those pcies that are not used. Since kernel has already disabled them, the following warnings appear: WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:952 clk_core_disable+0xe4/0x100 pcie2 already disabled Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.14.0 #0 Stack : 81661680 80082d00 807c0000 00000004 00000000 80a20000 80860000 80792380 814503d4 80862e83 00000000 1431b70 81454360 00000000 00000000 80792380 81431a08 ffffefff fffffea 00000000 81431a14 0000007b 80868820 ffffffff 80792380 1431c70 803d7a24 00000009 807f3a74 00000001 815df810 00000018 0000000 80a20000 ... Call Trace: [<80007ed8>] show_stack+0x28/0xf0 [<80381e40>] dump_stack_lvl+0x60/0x80 [<8002cf90>] __warn+0xcc/0x140 [<8002d090>] warn_slowpath_fmt+0x8c/0xac [<803d7a24>] clk_core_disable+0xe4/0x100 [<803da468>] clk_disable+0x38/0x58 [<804cb730>] mt7621_pci_probe+0x980/0xa50 [<8041e624>] platform_probe+0x50/0xbc [<8041bfe4>] really_probe.part.0+0xa8/0x340 [<8041c3dc>] driver_probe_device+0x4c/0x154 [<8041cb88>] __driver_attach+0xb4/0x1b4 [<80419a38>] bus_for_each_dev+0x68/0xa4 [<8041b1e8>] bus_add_driver+0x134/0x214 [<8041d3bc>] driver_register+0x98/0x154 [<80001648>] do_one_initcall+0x50/0x1a8 [<808ea1fc>] kernel_init_freeable+0x270/0x30c [<806dd9dc>] kernel_init+0x20/0x110 [<80002d98>] ret_from_kernel_thread+0x14/0x1c WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:810 clk_core_unprepare+0xf4/0x194 pcie2 already unprepared Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.14.0 #0 Stack : 81661680 80082d00 807c0000 00000004 00000000 00000000 81431bc4 80a20000 80860000 80792380 814503d4 80862e83 00000000 00000001 81431b70 81454360 00000000 00000000 80792380 81431a08 ffffefff 00000000 ffffffea 00000000 81431a14 0000009b 80868820 ffffffff 80792380 00000001 81431c70 803d7764 00000009 807f3a74 00000001 815df810 00000018 8040b36c 00000000 80a20000 ... Call Trace: [<80007ed8>] show_stack+0x28/0xf0 [<80381e40>] dump_stack_lvl+0x60/0x80 [<8002cf90>] __warn+0xcc/0x140 [<8002d090>] warn_slowpath_fmt+0x8c/0xac [<803d7764>] clk_core_unprepare+0xf4/0x194 [<803d97c4>] clk_unprepare+0x30/0x48 [<804cb738>] mt7621_pci_probe+0x988/0xa50 [<8041e624>] platform_probe+0x50/0xbc [<8041bfe4>] really_probe.part.0+0xa8/0x340 [<8041c3dc>] driver_probe_device+0x4c/0x154 [<8041cb88>] __driver_attach+0xb4/0x1b4 [<80419a38>] bus_for_each_dev+0x68/0xa4 [<8041b1e8>] bus_add_driver+0x134/0x214 [<8041d3bc>] driver_register+0x98/0x154 [<80001648>] do_one_initcall+0x50/0x1a8 [<808ea1fc>] kernel_init_freeable+0x270/0x30c [<806dd9dc>] kernel_init+0x20/0x110 [<80002d98>] ret_from_kernel_thread+0x14/0x1c Avoid to explicitly disable already disabled pcie gates fixes the problem. Fixes: cc4e864a5c ("staging: mt7621-pci: make use of kernel clock apis") Reported-by: DENG Qingfang <dqfext@gmail.com> Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Link: https://lore.kernel.org/r/20210727054058.10612-1-sergio.paracuellos@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-07-27 15:48:43 +02:00
..
Kconfig	MIPS: ralink: enable PCI support only if driver for mt7621 SoC is selected	2019-11-14 13:09:37 +08:00
Makefile	staging: add missing SPDX lines to Makefile files	2019-04-03 11:10:15 +02:00
TODO	staging: mt7621-pci: Update driver TODO file	2020-09-13 09:26:18 +02:00
mediatek,mt7621-pci.txt	staging: mt7621-pci: bindings: update doc accordly to last changes	2020-03-17 12:53:07 +01:00
pci-mt7621.c	staging: mt7621-pci: avoid to re-disable clock for those pcies not in use	2021-07-27 15:48:43 +02:00