Patch "MIPS: pci-mt7620: fix PLL lock check" has been added to the 5.4-stable tree

[gregkh at linuxfoundation.org]

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 at vger.kernel.org> know about it.


>From c15b99ae2ba9ea30da3c7cd4765b8a4707e530a6 Mon Sep 17 00:00:00 2001
From: Ilya Lipnitskiy <ilya.lipnitskiy at gmail.com>
Date: Sat, 6 Mar 2021 20:17:24 -0800
Subject: MIPS: pci-mt7620: fix PLL lock check

From: Ilya Lipnitskiy <ilya.lipnitskiy at gmail.com>

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 at gmail.com>
Cc: John Crispin <john at phrozen.org>
Cc: linux-mips at vger.kernel.org
Cc: linux-mediatek at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Cc: stable at vger.kernel.org
Signed-off-by: Thomas Bogendoerfer <tsbogend at alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 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 at gmail.com are

queue-5.4/mips-pci-mt7620-fix-pll-lock-check.patch
queue-5.4/mips-pci-rt2880-fix-slot-0-configuration.patch