From: Lucas Stach <l.stach@pengutronix.de>
To: Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@codeaurora.org>
Cc: Rob Herring <robh+dt@kernel.org>, Shawn Guo <shawnguo@kernel.org>,
Fabio Estevam <fabio.estevam@nxp.com>,
linux-clk@vger.kernel.org, devicetree@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de,
patchwork-lst@pengutronix.de,
"A . s . Dong" <aisheng.dong@nxp.com>,
linux-imx@nxp.com
Subject: [PATCH v2 2/4] clk: imx: add fractional PLL output clock
Date: Thu, 1 Feb 2018 18:54:10 +0100 [thread overview]
Message-ID: <20180201175412.9480-2-l.stach@pengutronix.de> (raw)
In-Reply-To: <20180201175412.9480-1-l.stach@pengutronix.de>
This is a new clock type introduced on i.MX8.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
---
drivers/clk/imx/Makefile | 1 +
drivers/clk/imx/clk-frac-pll.c | 229 +++++++++++++++++++++++++++++++++++++++++
drivers/clk/imx/clk.h | 3 +
3 files changed, 233 insertions(+)
create mode 100644 drivers/clk/imx/clk-frac-pll.c
diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
index f91f2b2e11cd..9892ae63539c 100644
--- a/drivers/clk/imx/Makefile
+++ b/drivers/clk/imx/Makefile
@@ -6,6 +6,7 @@ obj-y += \
clk-cpu.o \
clk-fixup-div.o \
clk-fixup-mux.o \
+ clk-frac-pll.o \
clk-gate-exclusive.o \
clk-gate2.o \
clk-pllv1.o \
diff --git a/drivers/clk/imx/clk-frac-pll.c b/drivers/clk/imx/clk-frac-pll.c
new file mode 100644
index 000000000000..30736d53dfbe
--- /dev/null
+++ b/drivers/clk/imx/clk-frac-pll.c
@@ -0,0 +1,229 @@
+/*
+ * Copyright 2017 NXP.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+
+#include "clk.h"
+
+#define PLL_CFG0 0x0
+#define PLL_CFG1 0x4
+
+#define PLL_LOCK_STATUS (0x1 << 31)
+#define PLL_CLKE 21
+#define PLL_PD 19
+#define PLL_BYPASS 14
+#define PLL_NEWDIV_VAL (1 << 12)
+#define PLL_NEWDIV_ACK (1 << 11)
+#define PLL_FRAC_DIV_MASK 0xffffff
+#define PLL_INT_DIV_MASK 0x7f
+#define PLL_FRAC_DENOM 0x1000000
+
+struct clk_frac_pll {
+ struct clk_hw hw;
+ void __iomem *base;
+};
+
+#define to_clk_frac_pll(_hw) container_of(_hw, struct clk_frac_pll, hw)
+
+static int clk_wait_lock(struct clk_frac_pll *pll)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(10);
+
+ /* Wait for PLL to lock */
+ do {
+ if (readl_relaxed(pll->base) & PLL_LOCK_STATUS)
+ break;
+ if (time_after(jiffies, timeout))
+ break;
+ } while (1);
+
+ return readl_relaxed(pll->base) & PLL_LOCK_STATUS ? 0 : -ETIMEDOUT;
+}
+
+static int clk_wait_ack(struct clk_frac_pll *pll)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(50);
+
+ /* return directly if the pll is in powerdown or in bypass */
+ if (readl_relaxed(pll->base) & ((1 << PLL_PD) | (1 << PLL_BYPASS)))
+ return 0;
+
+ /* Wait for the pll's divfi and divff to be reloaded */
+ do {
+ if (readl_relaxed(pll->base) & PLL_NEWDIV_ACK)
+ break;
+ if (time_after(jiffies, timeout))
+ break;
+ } while (1);
+
+ return readl_relaxed(pll->base) & PLL_NEWDIV_ACK ? 0 : ETIMEDOUT;
+}
+
+static int clk_pll_prepare(struct clk_hw *hw)
+{
+ struct clk_frac_pll *pll = to_clk_frac_pll(hw);
+ u32 val;
+
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ val &= ~(1 << PLL_PD);
+ writel_relaxed(val, pll->base + PLL_CFG0);
+
+ return clk_wait_lock(pll);
+}
+
+static void clk_pll_unprepare(struct clk_hw *hw)
+{
+ struct clk_frac_pll *pll = to_clk_frac_pll(hw);
+ u32 val;
+
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ val |= (1 << PLL_PD);
+ writel_relaxed(val, pll->base + PLL_CFG0);
+}
+
+static int clk_pll_is_prepared(struct clk_hw *hw)
+{
+ struct clk_frac_pll *pll = to_clk_frac_pll(hw);
+ u32 val;
+
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ return (val & (1 << PLL_PD)) ? 0 : 1;
+}
+
+static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_frac_pll *pll = to_clk_frac_pll(hw);
+ u32 val, divff, divfi, divq;
+ u64 temp64;
+
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ divq = ((val & 0x1f) + 1) * 2;
+ val = readl_relaxed(pll->base + PLL_CFG1);
+ divff = (val >> 7) & PLL_FRAC_DIV_MASK;
+ divfi = (val & PLL_INT_DIV_MASK);
+
+ temp64 = (u64)parent_rate * 8;
+ temp64 *= divff;
+ do_div(temp64, PLL_FRAC_DENOM);
+ temp64 /= divq;
+
+ return parent_rate * 8 * (divfi + 1) / divq + (unsigned long)temp64;
+}
+
+static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ u32 divff, divfi;
+ u64 temp64;
+ unsigned long parent_rate = *prate;
+
+ parent_rate *= 8;
+ rate *= 2;
+ divfi = rate / parent_rate;
+ temp64 = (u64)(rate - divfi * parent_rate);
+ temp64 *= PLL_FRAC_DENOM;
+ do_div(temp64, parent_rate);
+ divff = temp64;
+
+ temp64 = (u64)parent_rate;
+ temp64 *= divff;
+ do_div(temp64, PLL_FRAC_DENOM);
+
+ return (parent_rate * divfi + (unsigned long)temp64) / 2;
+}
+
+/*
+ * To simplify the clock calculation, we can keep the 'PLL_OUTPUT_VAL' at zero
+ * (means the PLL output will be divided by 2). So the PLL output can use
+ * the below formula:
+ * pllout = parent_rate * 8 / 2 * DIVF_VAL;
+ * where DIVF_VAL = 1 + DIVFI + DIVFF / 2^24.
+ */
+static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_frac_pll *pll = to_clk_frac_pll(hw);
+ u32 val, divfi, divff;
+ u64 temp64;
+ int ret;
+
+ parent_rate *= 8;
+ rate *= 2;
+ divfi = rate / parent_rate;
+ temp64 = (u64) (rate - divfi * parent_rate);
+ temp64 *= PLL_FRAC_DENOM;
+ do_div(temp64, parent_rate);
+ divff = temp64;
+
+ val = readl_relaxed(pll->base + PLL_CFG1);
+ val &= ~((PLL_FRAC_DIV_MASK << 7) | (PLL_INT_DIV_MASK));
+ val |= ((divff << 7) | (divfi - 1));
+ writel_relaxed(val, pll->base + PLL_CFG1);
+
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ val &= ~0x1f;
+ writel_relaxed(val, pll->base + PLL_CFG0);
+
+ /* Set the NEV_DIV_VAL to reload the DIVFI and DIVFF */
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ val |= PLL_NEWDIV_VAL;
+ writel_relaxed(val, pll->base + PLL_CFG0);
+
+ ret = clk_wait_ack(pll);
+
+ /* clear the NEV_DIV_VAL */
+ val = readl_relaxed(pll->base + PLL_CFG0);
+ val &= ~PLL_NEWDIV_VAL;
+ writel_relaxed(val, pll->base + PLL_CFG0);
+
+ return ret;
+}
+
+static const struct clk_ops clk_frac_pll_ops = {
+ .prepare = clk_pll_prepare,
+ .unprepare = clk_pll_unprepare,
+ .is_prepared = clk_pll_is_prepared,
+ .recalc_rate = clk_pll_recalc_rate,
+ .round_rate = clk_pll_round_rate,
+ .set_rate = clk_pll_set_rate,
+};
+
+struct clk *imx_clk_frac_pll(const char *name, const char *parent_name,
+ void __iomem *base)
+{
+ struct clk_frac_pll *pll;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ pll->base = base;
+ init.name = name;
+ init.ops = &clk_frac_pll_ops;
+ init.flags = 0;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ pll->hw.init = &init;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index d69c4bbf3597..287610902ea8 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -27,6 +27,9 @@ struct clk *imx_clk_pllv1(enum imx_pllv1_type type, const char *name,
struct clk *imx_clk_pllv2(const char *name, const char *parent,
void __iomem *base);
+struct clk *imx_clk_frac_pll(const char *name, const char *parent_name,
+ void __iomem *base);
+
enum imx_pllv3_type {
IMX_PLLV3_GENERIC,
IMX_PLLV3_SYS,
--
2.15.1
next prev parent reply other threads:[~2018-02-01 17:54 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-01 17:54 [PATCH v2 1/4] dt-bindings: add binding for i.MX8MQ CCM Lucas Stach
2018-02-01 17:54 ` Lucas Stach [this message]
2018-02-23 6:55 ` [PATCH v2 2/4] clk: imx: add fractional PLL output clock Shawn Guo
2018-02-28 10:14 ` Dong Aisheng
2018-02-01 17:54 ` [PATCH v2 4/4] clk: imx: add clock driver for i.MX8MQ CCM Lucas Stach
2018-02-23 9:20 ` Shawn Guo
2018-02-24 3:54 ` Shawn Guo
2018-02-28 12:23 ` Dong Aisheng
2018-03-15 21:33 ` Sascha Hauer
2018-03-16 10:10 ` Lucas Stach
2018-03-16 10:29 ` A.s. Dong
[not found] ` <20180201175412.9480-1-l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2018-02-01 17:54 ` [PATCH v2 3/4] clk: imx: add SCCG PLL type Lucas Stach
2018-02-23 8:46 ` Shawn Guo
2018-02-28 12:03 ` Dong Aisheng
2018-02-12 13:35 ` [PATCH v2 1/4] dt-bindings: add binding for i.MX8MQ CCM Shawn Guo
2018-02-22 3:55 ` Shawn Guo
2018-02-22 14:12 ` Shawn Guo
2018-02-23 9:29 ` Shawn Guo
2018-02-23 4:05 ` Shawn Guo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180201175412.9480-2-l.stach@pengutronix.de \
--to=l.stach@pengutronix.de \
--cc=aisheng.dong@nxp.com \
--cc=devicetree@vger.kernel.org \
--cc=fabio.estevam@nxp.com \
--cc=kernel@pengutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-imx@nxp.com \
--cc=mturquette@baylibre.com \
--cc=patchwork-lst@pengutronix.de \
--cc=robh+dt@kernel.org \
--cc=sboyd@codeaurora.org \
--cc=shawnguo@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).