Patch "clk: bcm2835: Protect sections updating shared registers" has been added to the 4.4-stable tree

Patch "clk: bcm2835: Protect sections updating shared registers" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    clk: bcm2835: Protect sections updating shared registers

to the 4.4-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:
     clk-bcm2835-protect-sections-updating-shared-registers.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 7997f3b2df751aab0b8e60149b226a32966c41ac Mon Sep 17 00:00:00 2001
From: Boris Brezillon <boris.brezillon@bootlin.com>
Date: Thu, 8 Feb 2018 14:43:36 +0100
Subject: clk: bcm2835: Protect sections updating shared registers

From: Boris Brezillon <boris.brezillon@bootlin.com>

commit 7997f3b2df751aab0b8e60149b226a32966c41ac upstream.

CM_PLLx and A2W_XOSC_CTRL registers are accessed by different clock
handlers and must be accessed with ->regs_lock held.
Update the sections where this protection is missing.

Fixes: 41691b8862e2 ("clk: bcm2835: Add support for programming the audio domain clocks")
Cc: <stable@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/clk/bcm/clk-bcm2835.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -912,8 +912,10 @@ static int bcm2835_pll_on(struct clk_hw
 		     ~A2W_PLL_CTRL_PWRDN);
 
 	/* Take the PLL out of reset. */
+	spin_lock(&cprman->regs_lock);
 	cprman_write(cprman, data->cm_ctrl_reg,
 		     cprman_read(cprman, data->cm_ctrl_reg) & ~CM_PLL_ANARST);
+	spin_unlock(&cprman->regs_lock);
 
 	/* Wait for the PLL to lock. */
 	timeout = ktime_add_ns(ktime_get(), LOCK_TIMEOUT_NS);
@@ -997,9 +999,11 @@ static int bcm2835_pll_set_rate(struct c
 	}
 
 	/* Unmask the reference clock from the oscillator. */
+	spin_lock(&cprman->regs_lock);
 	cprman_write(cprman, A2W_XOSC_CTRL,
 		     cprman_read(cprman, A2W_XOSC_CTRL) |
 		     data->reference_enable_mask);
+	spin_unlock(&cprman->regs_lock);
 
 	if (do_ana_setup_first)
 		bcm2835_pll_write_ana(cprman, data->ana_reg_base, ana);


Patches currently in stable-queue which might be from boris.brezillon@bootlin.com are

queue-4.4/clk-bcm2835-protect-sections-updating-shared-registers.patch