[PATCH v2 1/3] clk: tegra: Fix PLLE programming

[PATCH v2 1/3] clk: tegra: Fix PLLE programming

[Thierry Reding]

PLLE has M, N and P divider shift and width parameters that differ from
the defaults. Furthermore, when clearing the M, N and P divider fields
the corresponding masks were never shifted, thereby clearing only the
lowest bits of the register. This lead to a situation where the PLLE
programming would only work if the register hadn't been touched before.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v2:
- none

 drivers/clk/tegra/clk-pll.c | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 0d20241e0770..357911303315 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -58,9 +58,9 @@
 #define PLLDU_LFCON_SET_DIVN 600
 
 #define PLLE_BASE_DIVCML_SHIFT 24
-#define PLLE_BASE_DIVCML_WIDTH 4
+#define PLLE_BASE_DIVCML_MASK 0xf
 #define PLLE_BASE_DIVP_SHIFT 16
-#define PLLE_BASE_DIVP_WIDTH 7
+#define PLLE_BASE_DIVP_WIDTH 6
 #define PLLE_BASE_DIVN_SHIFT 8
 #define PLLE_BASE_DIVN_WIDTH 8
 #define PLLE_BASE_DIVM_SHIFT 0
@@ -730,8 +730,10 @@ static int clk_plle_enable(struct clk_hw *hw)
 	if (pll->params->flags & TEGRA_PLLE_CONFIGURE) {
 		/* configure dividers */
 		val = pll_readl_base(pll);
-		val &= ~(divm_mask(pll) | divn_mask(pll) | divp_mask(pll));
-		val &= ~(PLLE_BASE_DIVCML_WIDTH << PLLE_BASE_DIVCML_SHIFT);
+		val &= ~(divp_mask(pll) << PLLE_BASE_DIVP_SHIFT |
+			 divn_mask(pll) << PLLE_BASE_DIVN_SHIFT |
+			 divm_mask(pll) << PLLE_BASE_DIVM_SHIFT);
+		val &= ~(PLLE_BASE_DIVCML_MASK << PLLE_BASE_DIVCML_SHIFT);
 		val |= sel.m << pll->params->div_nmp->divm_shift;
 		val |= sel.n << pll->params->div_nmp->divn_shift;
 		val |= sel.p << pll->params->div_nmp->divp_shift;
@@ -745,6 +747,7 @@ static int clk_plle_enable(struct clk_hw *hw)
 	pll_writel_misc(val, pll);
 
 	val = readl(pll->clk_base + PLLE_SS_CTRL);
+	val &= ~PLLE_SS_COEFFICIENTS_MASK;
 	val |= PLLE_SS_DISABLE;
 	writel(val, pll->clk_base + PLLE_SS_CTRL);
 
@@ -1292,8 +1295,10 @@ static int clk_plle_tegra114_enable(struct clk_hw *hw)
 	pll_writel(val, PLLE_SS_CTRL, pll);
 
 	val = pll_readl_base(pll);
-	val &= ~(divm_mask(pll) | divn_mask(pll) | divp_mask(pll));
-	val &= ~(PLLE_BASE_DIVCML_WIDTH << PLLE_BASE_DIVCML_SHIFT);
+	val &= ~(divp_mask(pll) << PLLE_BASE_DIVP_SHIFT |
+		 divn_mask(pll) << PLLE_BASE_DIVN_SHIFT |
+		 divm_mask(pll) << PLLE_BASE_DIVM_SHIFT);
+	val &= ~(PLLE_BASE_DIVCML_MASK << PLLE_BASE_DIVCML_SHIFT);
 	val |= sel.m << pll->params->div_nmp->divm_shift;
 	val |= sel.n << pll->params->div_nmp->divn_shift;
 	val |= sel.cpcon << PLLE_BASE_DIVCML_SHIFT;
@@ -1410,6 +1415,15 @@ struct clk *tegra_clk_register_pll(const char *name, const char *parent_name,
 	return clk;
 }
 
+static struct div_nmp pll_e_nmp = {
+	.divn_shift = PLLE_BASE_DIVN_SHIFT,
+	.divn_width = PLLE_BASE_DIVN_WIDTH,
+	.divm_shift = PLLE_BASE_DIVM_SHIFT,
+	.divm_width = PLLE_BASE_DIVM_WIDTH,
+	.divp_shift = PLLE_BASE_DIVP_SHIFT,
+	.divp_width = PLLE_BASE_DIVP_WIDTH,
+};
+
 struct clk *tegra_clk_register_plle(const char *name, const char *parent_name,
 		void __iomem *clk_base, void __iomem *pmc,
 		unsigned long flags, struct tegra_clk_pll_params *pll_params,
@@ -1420,6 +1434,10 @@ struct clk *tegra_clk_register_plle(const char *name, const char *parent_name,
 
 	pll_params->flags |= TEGRA_PLL_LOCK_MISC | TEGRA_PLL_BYPASS;
 	pll_params->flags |= TEGRA_PLL_HAS_LOCK_ENABLE;
+
+	if (!pll_params->div_nmp)
+		pll_params->div_nmp = &pll_e_nmp;
+
 	pll = _tegra_init_pll(clk_base, pmc, pll_params, lock);
 	if (IS_ERR(pll))
 		return ERR_CAST(pll);
-- 
1.9.1

[PATCH v2 2/3] clk: tegra: Introduce divider mask and shift helpers

[Thierry Reding]

Add div{m,n,p}_shift() and div{m,n,p}_mask_shifted() helpers to make the
code that modifies the m-, n- and p-divider fields of PLLs shorter and
easier to read.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v2:
- new patch to address comment by Stephen

 drivers/clk/tegra/clk-pll.c | 44 ++++++++++++++++++++++++--------------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 357911303315..1187187a1cf2 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -183,6 +183,14 @@
 #define divp_mask(p) (p->params->flags & TEGRA_PLLU ? PLLU_POST_DIVP_MASK :\
 		      mask(p->params->div_nmp->divp_width))
 
+#define divm_shift(p) (p)->params->div_nmp->divm_shift
+#define divn_shift(p) (p)->params->div_nmp->divn_shift
+#define divp_shift(p) (p)->params->div_nmp->divp_shift
+
+#define divm_mask_shifted(p) (divm_mask(p) << divm_shift(p))
+#define divn_mask_shifted(p) (divn_mask(p) << divn_shift(p))
+#define divp_mask_shifted(p) (divp_mask(p) << divp_shift(p))
+
 #define divm_max(p) (divm_mask(p))
 #define divn_max(p) (divn_mask(p))
 #define divp_max(p) (1 << (divp_mask(p)))
@@ -476,13 +484,12 @@ static void _update_pll_mnp(struct tegra_clk_pll *pll,
 	} else {
 		val = pll_readl_base(pll);
 
-		val &= ~((divm_mask(pll) << div_nmp->divm_shift) |
-		 (divn_mask(pll) << div_nmp->divn_shift) |
-		 (divp_mask(pll) << div_nmp->divp_shift));
+		val &= ~(divm_mask_shifted(pll) | divn_mask_shifted(pll) |
+			 divp_mask_shifted(pll));
 
-		val |= ((cfg->m << div_nmp->divm_shift) |
-			(cfg->n << div_nmp->divn_shift) |
-			(cfg->p << div_nmp->divp_shift));
+		val |= (cfg->m << divm_shift(pll)) |
+		       (cfg->n << divn_shift(pll)) |
+		       (cfg->p << divp_shift(pll));
 
 		pll_writel_base(val, pll);
 	}
@@ -730,13 +737,12 @@ static int clk_plle_enable(struct clk_hw *hw)
 	if (pll->params->flags & TEGRA_PLLE_CONFIGURE) {
 		/* configure dividers */
 		val = pll_readl_base(pll);
-		val &= ~(divp_mask(pll) << PLLE_BASE_DIVP_SHIFT |
-			 divn_mask(pll) << PLLE_BASE_DIVN_SHIFT |
-			 divm_mask(pll) << PLLE_BASE_DIVM_SHIFT);
+		val &= ~(divp_mask_shifted(pll) | divn_mask_shifted(pll) |
+			 divm_mask_shifted(pll));
 		val &= ~(PLLE_BASE_DIVCML_MASK << PLLE_BASE_DIVCML_SHIFT);
-		val |= sel.m << pll->params->div_nmp->divm_shift;
-		val |= sel.n << pll->params->div_nmp->divn_shift;
-		val |= sel.p << pll->params->div_nmp->divp_shift;
+		val |= sel.m << divm_shift(pll);
+		val |= sel.n << divn_shift(pll);
+		val |= sel.p << divp_shift(pll);
 		val |= sel.cpcon << PLLE_BASE_DIVCML_SHIFT;
 		pll_writel_base(val, pll);
 	}
@@ -1295,12 +1301,11 @@ static int clk_plle_tegra114_enable(struct clk_hw *hw)
 	pll_writel(val, PLLE_SS_CTRL, pll);
 
 	val = pll_readl_base(pll);
-	val &= ~(divp_mask(pll) << PLLE_BASE_DIVP_SHIFT |
-		 divn_mask(pll) << PLLE_BASE_DIVN_SHIFT |
-		 divm_mask(pll) << PLLE_BASE_DIVM_SHIFT);
+	val &= ~(divp_mask_shifted(pll) | divn_mask_shifted(pll) |
+		 divm_mask_shifted(pll));
 	val &= ~(PLLE_BASE_DIVCML_MASK << PLLE_BASE_DIVCML_SHIFT);
-	val |= sel.m << pll->params->div_nmp->divm_shift;
-	val |= sel.n << pll->params->div_nmp->divn_shift;
+	val |= sel.m << divm_shift(pll);
+	val |= sel.n << divn_shift(pll);
 	val |= sel.cpcon << PLLE_BASE_DIVCML_SHIFT;
 	pll_writel_base(val, pll);
 	udelay(1);
@@ -1575,9 +1580,8 @@ struct clk *tegra_clk_register_pllre(const char *name, const char *parent_name,
 		int m;
 
 		m = _pll_fixed_mdiv(pll_params, parent_rate);
-		val = m << PLL_BASE_DIVM_SHIFT;
-		val |= (pll_params->vco_min / parent_rate)
-				<< PLL_BASE_DIVN_SHIFT;
+		val = m << divm_shift(pll);
+		val |= (pll_params->vco_min / parent_rate) << divn_shift(pll);
 		pll_writel_base(val, pll);
 	}
 
-- 
1.9.1

[PATCH v2 3/3] clk: tegra: Fix enabling of PLLE

[Thierry Reding]

When enabling the PLLE as its final step, clk_plle_enable() would
accidentally OR in the value previously written to the PLLE_SS_CTRL
register.

Signed-off-by: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
Changes in v2:
- new patch

 drivers/clk/tegra/clk-pll.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 1187187a1cf2..7a1b70dac824 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -757,7 +757,7 @@ static int clk_plle_enable(struct clk_hw *hw)
 	val |= PLLE_SS_DISABLE;
 	writel(val, pll->clk_base + PLLE_SS_CTRL);
 
-	val |= pll_readl_base(pll);
+	val = pll_readl_base(pll);
 	val |= (PLL_BASE_BYPASS | PLL_BASE_ENABLE);
 	pll_writel_base(val, pll);
 
-- 
1.9.1

Re: [PATCH v2 1/3] clk: tegra: Fix PLLE programming

[Stephen Warren]

On 04/04/2014 07:55 AM, Thierry Reding wrote:
> PLLE has M, N and P divider shift and width parameters that differ from
> the defaults. Furthermore, when clearing the M, N and P divider fields
> the corresponding masks were never shifted, thereby clearing only the
> lowest bits of the register. This lead to a situation where the PLLE
> programming would only work if the register hadn't been touched before.

The series,
Acked-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

(I might have squashed patches 1 and 2 together, but no matter)

I expect these patches should be CC: stable when applied?

Re: [PATCH v2 1/3] clk: tegra: Fix PLLE programming

[Peter De Schrijver]

On Fri, Apr 04, 2014 at 03:55:13PM +0200, Thierry Reding wrote:
> PLLE has M, N and P divider shift and width parameters that differ from
> the defaults. Furthermore, when clearing the M, N and P divider fields
> the corresponding masks were never shifted, thereby clearing only the
> lowest bits of the register. This lead to a situation where the PLLE
> programming would only work if the register hadn't been touched before.
> 

Will take this into tegra-clk-next. Mike, given that this is bug fix for
a feature which is supposed to work, I think it's appropriate to try to get
this into 3.15 still. I will make a pull-request on 3.15-rc1 as soon as it
appears.

Cheers,

Peter.