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Patch "clk: iproc: Fix PLL output frequency calculation" has been added to the 4.3-stable tree

PATCH [email protected] 1 participant 1 message Dec 7, 2015

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Stable branch Common clk Broadcom iproc Arm architecture
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This is a note to let you know that I've just added the patch titled

clk: iproc: Fix PLL output frequency calculation

to the 4.3-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-iproc-fix-pll-output-frequency-calculation.patch
and it can be found in the queue-4.3 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 63243a4da7d0dfa19dcacd0a529782eeb2f86f92 Mon Sep 17 00:00:00 2001

From: Simran Rai <[email protected]>
Date: Mon, 19 Oct 2015 15:27:19 -0700
Subject: clk: iproc: Fix PLL output frequency calculation

From: Simran Rai <[email protected]>

commit 63243a4da7d0dfa19dcacd0a529782eeb2f86f92 upstream.

This patch affects the clocks that use fractional ndivider in their PLL output frequency calculation. Instead of 2^20 divide factor, the clock's ndiv integer shift was used. Fixed the bug by replacing ndiv integer shift with 2^20 factor.

Signed-off-by Simran Rai <[email protected]>
Signed-off-by Ray Jui <[email protected]>
Reviewed-by Scott Branden <[email protected]>
Fixes 5fe225c105fd ("clk: iproc: add initial common clock support")
Signed-off-by Michael Turquette <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 drivers/clk/bcm/clk-iproc-pll.c |   13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)
drivers/clk/bcm/clk-iproc-pll.c +5 -8
@@ -345,8 +345,8 @@ static unsigned long iproc_pll_recalc_ra
 	struct iproc_pll *pll = clk->pll;
 	const struct iproc_pll_ctrl *ctrl = pll->ctrl;
 	u32 val;
-	u64 ndiv;
-	unsigned int ndiv_int, ndiv_frac, pdiv;
+	u64 ndiv, ndiv_int, ndiv_frac;
+	unsigned int pdiv;
 
 	if (parent_rate == 0)
 		return 0;

@@ -366,22 +366,19 @@ static unsigned long iproc_pll_recalc_ra
 	val = readl(pll->pll_base + ctrl->ndiv_int.offset);
 	ndiv_int = (val >> ctrl->ndiv_int.shift) &
 		bit_mask(ctrl->ndiv_int.width);
-	ndiv = (u64)ndiv_int << ctrl->ndiv_int.shift;
+	ndiv = ndiv_int << 20;
 
 	if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
 		val = readl(pll->pll_base + ctrl->ndiv_frac.offset);
 		ndiv_frac = (val >> ctrl->ndiv_frac.shift) &
 			bit_mask(ctrl->ndiv_frac.width);
-
-		if (ndiv_frac != 0)
-			ndiv = ((u64)ndiv_int << ctrl->ndiv_int.shift) |
-				ndiv_frac;
+		ndiv += ndiv_frac;
 	}
 
 	val = readl(pll->pll_base + ctrl->pdiv.offset);
 	pdiv = (val >> ctrl->pdiv.shift) & bit_mask(ctrl->pdiv.width);
 
-	clk->rate = (ndiv * parent_rate) >> ctrl->ndiv_int.shift;
+	clk->rate = (ndiv * parent_rate) >> 20;
 
 	if (pdiv == 0)
 		clk->rate *= 2;

Patches currently in stable-queue which might be from [email protected] are

queue-4.3/clk-iproc-fix-pll-output-frequency-calculation.patch