[PATCH 2/3] ARM i.MX6: Fix ethernet PLL clocks

Sascha Hauer s.hauer at pengutronix.de
Thu Nov 22 07:35:35 EST 2012


On Thu, Nov 22, 2012 at 07:32:28PM +0800, Shawn Guo wrote:
> On Thu, Nov 22, 2012 at 10:59:17AM +0100, Sascha Hauer wrote:
> > In current code the ethernet PLL is not handled correctly. The PLL runs at 500MHz
> > and has different outputs. Only the enet reference clock is implemented. This
> > patch changes the PLL so that it outputs 500MHz and adds the additional outputs
> > as dividers. This now matches the datasheet which says:
> > 
> > > This PLL synthesizes a low jitter clock from 24 MHz reference clock.
> > > The PLL outputs a 500 MHz clock. The reference clocks generated by this PLL are:
> > >  • Ref_PCIe = 125 MHz
> > >  • Ref_SATA = 100 MHz
> > >  • Ref_ethernet, which is configurable based on the PLL_ENET[1:0] register field.
> > 
> > Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> > ---
> >  .../devicetree/bindings/clock/imx6q-clock.txt      |    5 ++
> >  arch/arm/mach-imx/clk-imx6q.c                      |   21 ++++++-
> >  arch/arm/mach-imx/clk-pllv3.c                      |   63 +-------------------
> >  3 files changed, 25 insertions(+), 64 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/clock/imx6q-clock.txt b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> > index bb71d4f..d77b4e6 100644
> > --- a/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> > +++ b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
> > @@ -198,6 +198,11 @@ clocks and IDs.
> >  	usbphy2			183
> >  	ldb_di0_div_3_5		184
> >  	ldb_di1_div_3_5		185
> > +	sata_ref		186
> > +	sata_ref_100m		187
> > +	pcie_ref		188
> > +	pcie_ref_125m		189
> > +	enet_ref		190
> >  
> >  Examples:
> >  
> > diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c
> > index 4066365..622a299 100644
> > --- a/arch/arm/mach-imx/clk-imx6q.c
> > +++ b/arch/arm/mach-imx/clk-imx6q.c
> > @@ -153,6 +153,7 @@ enum mx6q_clks {
> >  	usdhc4, vdo_axi, vpu_axi, cko1, pll1_sys, pll2_bus, pll3_usb_otg,
> >  	pll4_audio, pll5_video, pll8_mlb, pll7_usb_host, pll6_enet, ssi1_ipg,
> >  	ssi2_ipg, ssi3_ipg, rom, usbphy1, usbphy2, ldb_di0_div_3_5, ldb_di1_div_3_5,
> > +	sata_ref, sata_ref_100m, pcie_ref, pcie_ref_125m, enet_ref,
> >  	clk_max
> >  };
> >  
> > @@ -163,6 +164,13 @@ static enum mx6q_clks const clks_init_on[] __initconst = {
> >  	mmdc_ch0_axi, rom,
> >  };
> >  
> > +static struct clk_div_table clk_enet_ref_table[] = {
> > +	{ .val = 0, .div = 20, },
> > +	{ .val = 1, .div = 10, },
> > +	{ .val = 2, .div = 5, },
> > +	{ .val = 3, .div = 4, },
> > +};
> > +
> >  int __init mx6q_clocks_init(void)
> >  {
> >  	struct device_node *np;
> > @@ -195,13 +203,22 @@ int __init mx6q_clocks_init(void)
> >  	clk[pll3_usb_otg]  = imx_clk_pllv3(IMX_PLLV3_USB,	"pll3_usb_otg",	"osc", base + 0x10, 0x2000,   0x3);
> >  	clk[pll4_audio]    = imx_clk_pllv3(IMX_PLLV3_AV,	"pll4_audio",	"osc", base + 0x70, 0x2000,   0x7f);
> >  	clk[pll5_video]    = imx_clk_pllv3(IMX_PLLV3_AV,	"pll5_video",	"osc", base + 0xa0, 0x2000,   0x7f);
> > -	clk[pll6_enet]     = imx_clk_pllv3(IMX_PLLV3_ENET,	"pll6_enet",	"osc", base + 0xe0, 0x182000, 0x3);
> > +	clk[pll6_enet]     = imx_clk_pllv3(IMX_PLLV3_ENET,	"pll6_enet",	"osc", base + 0xe0, 0x2000,   0x3);
> >  	clk[pll7_usb_host] = imx_clk_pllv3(IMX_PLLV3_USB,	"pll7_usb_host","osc", base + 0x20, 0x2000,   0x3);
> > -	clk[pll8_mlb]      = imx_clk_pllv3(IMX_PLLV3_MLB,	"pll8_mlb",	"osc", base + 0xd0, 0x2000,   0x0);
> 
> It gets removed by accident?

Yes, I screwed it up while rebasing. Find an updated version attached.

> 
> Otherwise, for the series:
> 
> Acked-by: Shawn Guo <shawn.guo at linaro.org>

Thanks.

Sascha

8<----------------------------------------------------

>From 4de7de851c6666c4dca4f36acbc7f9b802ea7d7f Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer at pengutronix.de>
Date: Wed, 21 Nov 2012 14:42:31 +0100
Subject: [PATCH 2/3] ARM i.MX6: Fix ethernet PLL clocks
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

In current code the ethernet PLL is not handled correctly. The PLL runs at 500MHz
and has different outputs. Only the enet reference clock is implemented. This
patch changes the PLL so that it outputs 500MHz and adds the additional outputs
as dividers. This now matches the datasheet which says:

> This PLL synthesizes a low jitter clock from 24 MHz reference clock.
> The PLL outputs a 500 MHz clock. The reference clocks generated by this PLL are:
>  • Ref_PCIe = 125 MHz
>  • Ref_SATA = 100 MHz
>  • Ref_ethernet, which is configurable based on the PLL_ENET[1:0] register field.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 .../devicetree/bindings/clock/imx6q-clock.txt      |    5 ++
 arch/arm/mach-imx/clk-imx6q.c                      |   20 ++++++-
 arch/arm/mach-imx/clk-pllv3.c                      |   63 +-------------------
 3 files changed, 25 insertions(+), 63 deletions(-)

diff --git a/Documentation/devicetree/bindings/clock/imx6q-clock.txt b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
index bb71d4f..d77b4e6 100644
--- a/Documentation/devicetree/bindings/clock/imx6q-clock.txt
+++ b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
@@ -198,6 +198,11 @@ clocks and IDs.
 	usbphy2			183
 	ldb_di0_div_3_5		184
 	ldb_di1_div_3_5		185
+	sata_ref		186
+	sata_ref_100m		187
+	pcie_ref		188
+	pcie_ref_125m		189
+	enet_ref		190
 
 Examples:
 
diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c
index 4066365..a579a1c 100644
--- a/arch/arm/mach-imx/clk-imx6q.c
+++ b/arch/arm/mach-imx/clk-imx6q.c
@@ -153,6 +153,7 @@ enum mx6q_clks {
 	usdhc4, vdo_axi, vpu_axi, cko1, pll1_sys, pll2_bus, pll3_usb_otg,
 	pll4_audio, pll5_video, pll8_mlb, pll7_usb_host, pll6_enet, ssi1_ipg,
 	ssi2_ipg, ssi3_ipg, rom, usbphy1, usbphy2, ldb_di0_div_3_5, ldb_di1_div_3_5,
+	sata_ref, sata_ref_100m, pcie_ref, pcie_ref_125m, enet_ref,
 	clk_max
 };
 
@@ -163,6 +164,13 @@ static enum mx6q_clks const clks_init_on[] __initconst = {
 	mmdc_ch0_axi, rom,
 };
 
+static struct clk_div_table clk_enet_ref_table[] = {
+	{ .val = 0, .div = 20, },
+	{ .val = 1, .div = 10, },
+	{ .val = 2, .div = 5, },
+	{ .val = 3, .div = 4, },
+};
+
 int __init mx6q_clocks_init(void)
 {
 	struct device_node *np;
@@ -195,13 +203,23 @@ int __init mx6q_clocks_init(void)
 	clk[pll3_usb_otg]  = imx_clk_pllv3(IMX_PLLV3_USB,	"pll3_usb_otg",	"osc", base + 0x10, 0x2000,   0x3);
 	clk[pll4_audio]    = imx_clk_pllv3(IMX_PLLV3_AV,	"pll4_audio",	"osc", base + 0x70, 0x2000,   0x7f);
 	clk[pll5_video]    = imx_clk_pllv3(IMX_PLLV3_AV,	"pll5_video",	"osc", base + 0xa0, 0x2000,   0x7f);
-	clk[pll6_enet]     = imx_clk_pllv3(IMX_PLLV3_ENET,	"pll6_enet",	"osc", base + 0xe0, 0x182000, 0x3);
+	clk[pll6_enet]     = imx_clk_pllv3(IMX_PLLV3_ENET,	"pll6_enet",	"osc", base + 0xe0, 0x2000,   0x3);
 	clk[pll7_usb_host] = imx_clk_pllv3(IMX_PLLV3_USB,	"pll7_usb_host","osc", base + 0x20, 0x2000,   0x3);
 	clk[pll8_mlb]      = imx_clk_pllv3(IMX_PLLV3_MLB,	"pll8_mlb",	"osc", base + 0xd0, 0x2000,   0x0);
 
 	clk[usbphy1] = imx_clk_gate("usbphy1", "pll3_usb_otg", base + 0x10, 6);
 	clk[usbphy2] = imx_clk_gate("usbphy2", "pll7_usb_host", base + 0x20, 6);
 
+	clk[sata_ref] = imx_clk_fixed_factor("sata_ref", "pll6_enet", 1, 5);
+	clk[pcie_ref] = imx_clk_fixed_factor("pcie_ref", "pll6_enet", 1, 4);
+
+	clk[sata_ref_100m] = imx_clk_gate("sata_ref_100m", "sata_ref", base + 0xe0, 20);
+	clk[pcie_ref_125m] = imx_clk_gate("pcie_ref_125m", "pcie_ref", base + 0xe0, 19);
+
+	clk[enet_ref] = clk_register_divider_table(NULL, "enet_ref", "pll6_enet", 0,
+			base + 0xe0, 0, 2, 0, clk_enet_ref_table,
+			&imx_ccm_lock);
+
 	/*                                name              parent_name        reg       idx */
 	clk[pll2_pfd0_352m] = imx_clk_pfd("pll2_pfd0_352m", "pll2_bus",     base + 0x100, 0);
 	clk[pll2_pfd1_594m] = imx_clk_pfd("pll2_pfd1_594m", "pll2_bus",     base + 0x100, 1);
diff --git a/arch/arm/mach-imx/clk-pllv3.c b/arch/arm/mach-imx/clk-pllv3.c
index 36aac94..59e7433 100644
--- a/arch/arm/mach-imx/clk-pllv3.c
+++ b/arch/arm/mach-imx/clk-pllv3.c
@@ -287,66 +287,7 @@ static const struct clk_ops clk_pllv3_av_ops = {
 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
 						unsigned long parent_rate)
 {
-	struct clk_pllv3 *pll = to_clk_pllv3(hw);
-	u32 div = readl_relaxed(pll->base) & pll->div_mask;
-
-	switch (div) {
-	case 0:
-		return 25000000;
-	case 1:
-		return 50000000;
-	case 2:
-		return 100000000;
-	case 3:
-		return 125000000;
-	}
-
-	return 0;
-}
-
-static long clk_pllv3_enet_round_rate(struct clk_hw *hw, unsigned long rate,
-				      unsigned long *prate)
-{
-	if (rate >= 125000000)
-		rate = 125000000;
-	else if (rate >= 100000000)
-		rate = 100000000;
-	else if (rate >= 50000000)
-		rate = 50000000;
-	else
-		rate = 25000000;
-	return rate;
-}
-
-static int clk_pllv3_enet_set_rate(struct clk_hw *hw, unsigned long rate,
-		unsigned long parent_rate)
-{
-	struct clk_pllv3 *pll = to_clk_pllv3(hw);
-	u32 val, div;
-
-	switch (rate) {
-	case 25000000:
-		div = 0;
-		break;
-	case 50000000:
-		div = 1;
-		break;
-	case 100000000:
-		div = 2;
-		break;
-	case 125000000:
-		div = 3;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	val = readl_relaxed(pll->base);
-	val &= ~pll->div_mask;
-	val |= div;
-	writel_relaxed(val, pll->base);
-
-	return 0;
+	return 500000000;
 }
 
 static const struct clk_ops clk_pllv3_enet_ops = {
@@ -355,8 +296,6 @@ static const struct clk_ops clk_pllv3_enet_ops = {
 	.enable		= clk_pllv3_enable,
 	.disable	= clk_pllv3_disable,
 	.recalc_rate	= clk_pllv3_enet_recalc_rate,
-	.round_rate	= clk_pllv3_enet_round_rate,
-	.set_rate	= clk_pllv3_enet_set_rate,
 };
 
 static const struct clk_ops clk_pllv3_mlb_ops = {
-- 
1.7.10.4

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