This is a note to let you know that I've just added the patch titled MIPS: pci-mt7620: fix PLL lock check to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mips-pci-mt7620-fix-pll-lock-check.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c15b99ae2ba9ea30da3c7cd4765b8a4707e530a6 Mon Sep 17 00:00:00 2001 From: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx> Date: Sat, 6 Mar 2021 20:17:24 -0800 Subject: MIPS: pci-mt7620: fix PLL lock check From: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx> commit c15b99ae2ba9ea30da3c7cd4765b8a4707e530a6 upstream. Upstream a long-standing OpenWrt patch [0] that fixes MT7620 PCIe PLL lock check. The existing code checks the wrong register bit: PPLL_SW_SET is not defined in PPLL_CFG1 and bit 31 of PPLL_CFG1 is marked as reserved in the MT7620 Programming Guide. The correct bit to check for PLL lock is PPLL_LD (bit 23). Also reword the error message for clarity. Without this change it is unlikely that this driver ever worked with mainline kernel. [0]: https://lists.infradead.org/pipermail/lede-commits/2017-July/004441.html Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx> Cc: John Crispin <john@xxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx Cc: linux-mediatek@xxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/pci/pci-mt7620.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/mips/pci/pci-mt7620.c +++ b/arch/mips/pci/pci-mt7620.c @@ -30,6 +30,7 @@ #define RALINK_GPIOMODE 0x60 #define PPLL_CFG1 0x9c +#define PPLL_LD BIT(23) #define PPLL_DRV 0xa0 #define PDRV_SW_SET BIT(31) @@ -239,8 +240,8 @@ static int mt7620_pci_hw_init(struct pla rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1); mdelay(100); - if (!(rt_sysc_r32(PPLL_CFG1) & PDRV_SW_SET)) { - dev_err(&pdev->dev, "MT7620 PPLL unlock\n"); + if (!(rt_sysc_r32(PPLL_CFG1) & PPLL_LD)) { + dev_err(&pdev->dev, "pcie PLL not locked, aborting init\n"); reset_control_assert(rstpcie0); rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); return -1; Patches currently in stable-queue which might be from ilya.lipnitskiy@xxxxxxxxx are queue-5.4/mips-pci-mt7620-fix-pll-lock-check.patch queue-5.4/mips-pci-rt2880-fix-slot-0-configuration.patch