From: sboyd@codeaurora.org (Stephen Boyd)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 07/15] clk: qcom: Add support for High-Frequency PLLs (HFPLLs)
Date: Fri, 5 Sep 2014 15:47:27 -0700 [thread overview]
Message-ID: <1409957256-23729-9-git-send-email-sboyd@codeaurora.org> (raw)
In-Reply-To: <1409957256-23729-1-git-send-email-sboyd@codeaurora.org>
HFPLLs are the main frequency source for Krait CPU clocks. Add
support for changing the rate of these PLLs.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/qcom/Makefile | 1 +
drivers/clk/qcom/clk-hfpll.c | 253 +++++++++++++++++++++++++++++++++++++++++++
drivers/clk/qcom/clk-hfpll.h | 54 +++++++++
3 files changed, 308 insertions(+)
create mode 100644 drivers/clk/qcom/clk-hfpll.c
create mode 100644 drivers/clk/qcom/clk-hfpll.h
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index 783cfb24faa4..f1e54065e4dc 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -6,6 +6,7 @@ clk-qcom-y += clk-pll.o
clk-qcom-y += clk-rcg.o
clk-qcom-y += clk-rcg2.o
clk-qcom-y += clk-branch.o
+clk-qcom-y += clk-hfpll.o
clk-qcom-y += reset.o
obj-$(CONFIG_APQ_GCC_8084) += gcc-apq8084.o
diff --git a/drivers/clk/qcom/clk-hfpll.c b/drivers/clk/qcom/clk-hfpll.c
new file mode 100644
index 000000000000..367eb95f1477
--- /dev/null
+++ b/drivers/clk/qcom/clk-hfpll.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/spinlock.h>
+
+#include "clk-regmap.h"
+#include "clk-hfpll.h"
+
+#define PLL_OUTCTRL BIT(0)
+#define PLL_BYPASSNL BIT(1)
+#define PLL_RESET_N BIT(2)
+
+/* Initialize a HFPLL at a given rate and enable it. */
+static void __clk_hfpll_init_once(struct clk_hw *hw)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+
+ if (likely(h->init_done))
+ return;
+
+ /* Configure PLL parameters for integer mode. */
+ if (hd->config_val)
+ regmap_write(regmap, hd->config_reg, hd->config_val);
+ regmap_write(regmap, hd->m_reg, 0);
+ regmap_write(regmap, hd->n_reg, 1);
+
+ if (hd->user_reg) {
+ u32 regval = hd->user_val;
+ unsigned long rate;
+
+ rate = __clk_get_rate(hw->clk);
+
+ /* Pick the right VCO. */
+ if (hd->user_vco_mask && rate > hd->low_vco_max_rate)
+ regval |= hd->user_vco_mask;
+ regmap_write(regmap, hd->user_reg, regval);
+ }
+
+ if (hd->droop_reg)
+ regmap_write(regmap, hd->droop_reg, hd->droop_val);
+
+ h->init_done = true;
+}
+
+static void __clk_hfpll_enable(struct clk_hw *hw)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ u32 val;
+
+ __clk_hfpll_init_once(hw);
+
+ /* Disable PLL bypass mode. */
+ regmap_update_bits(regmap, hd->mode_reg, PLL_BYPASSNL, PLL_BYPASSNL);
+
+ /*
+ * H/W requires a 5us delay between disabling the bypass and
+ * de-asserting the reset. Delay 10us just to be safe.
+ */
+ udelay(10);
+
+ /* De-assert active-low PLL reset. */
+ regmap_update_bits(regmap, hd->mode_reg, PLL_RESET_N, PLL_RESET_N);
+
+ /* Wait for PLL to lock. */
+ if (hd->status_reg) {
+ do {
+ regmap_read(regmap, hd->status_reg, &val);
+ } while (!(val & BIT(hd->lock_bit)));
+ } else {
+ udelay(60);
+ }
+
+ /* Enable PLL output. */
+ regmap_update_bits(regmap, hd->mode_reg, PLL_OUTCTRL, PLL_OUTCTRL);
+}
+
+/* Enable an already-configured HFPLL. */
+static int clk_hfpll_enable(struct clk_hw *hw)
+{
+ unsigned long flags;
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ u32 mode;
+
+ spin_lock_irqsave(&h->lock, flags);
+ regmap_read(regmap, hd->mode_reg, &mode);
+ if (!(mode & (PLL_BYPASSNL | PLL_RESET_N | PLL_OUTCTRL)))
+ __clk_hfpll_enable(hw);
+ spin_unlock_irqrestore(&h->lock, flags);
+
+ return 0;
+}
+
+static void __clk_hfpll_disable(struct clk_hfpll *h)
+{
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+
+ /*
+ * Disable the PLL output, disable test mode, enable the bypass mode,
+ * and assert the reset.
+ */
+ regmap_update_bits(regmap, hd->mode_reg,
+ PLL_BYPASSNL | PLL_RESET_N | PLL_OUTCTRL, 0);
+}
+
+static void clk_hfpll_disable(struct clk_hw *hw)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ unsigned long flags;
+
+ spin_lock_irqsave(&h->lock, flags);
+ __clk_hfpll_disable(h);
+ spin_unlock_irqrestore(&h->lock, flags);
+}
+
+static long clk_hfpll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ unsigned long rrate;
+
+ rate = clamp(rate, hd->min_rate, hd->max_rate);
+
+ rrate = DIV_ROUND_UP(rate, *parent_rate) * *parent_rate;
+ if (rrate > hd->max_rate)
+ rrate -= *parent_rate;
+
+ return rrate;
+}
+
+/*
+ * For optimization reasons, assumes no downstream clocks are actively using
+ * it.
+ */
+static int clk_hfpll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ unsigned long flags;
+ u32 l_val, val;
+ bool enabled;
+
+ l_val = rate / parent_rate;
+
+ spin_lock_irqsave(&h->lock, flags);
+
+ enabled = __clk_is_enabled(hw->clk);
+ if (enabled)
+ __clk_hfpll_disable(h);
+
+ /* Pick the right VCO. */
+ if (hd->user_reg && hd->user_vco_mask) {
+ regmap_read(regmap, hd->user_reg, &val);
+ if (rate <= hd->low_vco_max_rate)
+ val &= ~hd->user_vco_mask;
+ else
+ val |= hd->user_vco_mask;
+ regmap_write(regmap, hd->user_reg, val);
+ }
+
+ regmap_write(regmap, hd->l_reg, l_val);
+
+ if (enabled)
+ __clk_hfpll_enable(hw);
+
+ spin_unlock_irqrestore(&h->lock, flags);
+
+ return 0;
+}
+
+static unsigned long clk_hfpll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ u32 l_val;
+
+ regmap_read(regmap, hd->l_reg, &l_val);
+
+ return l_val * parent_rate;
+}
+
+static void clk_hfpll_init(struct clk_hw *hw)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ u32 mode, status;
+
+ regmap_read(regmap, hd->mode_reg, &mode);
+ if (mode != (PLL_BYPASSNL | PLL_RESET_N | PLL_OUTCTRL)) {
+ __clk_hfpll_init_once(hw);
+ return;
+ }
+
+ if (hd->status_reg) {
+ regmap_read(regmap, hd->status_reg, &status);
+ if (!(status & BIT(hd->lock_bit))) {
+ WARN(1, "HFPLL %s is ON, but not locked!\n",
+ __clk_get_name(hw->clk));
+ clk_hfpll_disable(hw);
+ __clk_hfpll_init_once(hw);
+ }
+ }
+}
+
+static int hfpll_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hfpll *h = to_clk_hfpll(hw);
+ struct hfpll_data const *hd = h->d;
+ struct regmap *regmap = h->clkr.regmap;
+ u32 mode;
+
+ regmap_read(regmap, hd->mode_reg, &mode);
+ mode &= 0x7;
+ return mode == (PLL_BYPASSNL | PLL_RESET_N | PLL_OUTCTRL);
+}
+
+const struct clk_ops clk_ops_hfpll = {
+ .enable = clk_hfpll_enable,
+ .disable = clk_hfpll_disable,
+ .is_enabled = hfpll_is_enabled,
+ .round_rate = clk_hfpll_round_rate,
+ .set_rate = clk_hfpll_set_rate,
+ .recalc_rate = clk_hfpll_recalc_rate,
+ .init = clk_hfpll_init,
+};
+EXPORT_SYMBOL_GPL(clk_ops_hfpll);
diff --git a/drivers/clk/qcom/clk-hfpll.h b/drivers/clk/qcom/clk-hfpll.h
new file mode 100644
index 000000000000..48c18d664f4e
--- /dev/null
+++ b/drivers/clk/qcom/clk-hfpll.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#ifndef __QCOM_CLK_HFPLL_H__
+#define __QCOM_CLK_HFPLL_H__
+
+#include <linux/clk-provider.h>
+#include <linux/spinlock.h>
+#include "clk-regmap.h"
+
+struct hfpll_data {
+ u32 mode_reg;
+ u32 l_reg;
+ u32 m_reg;
+ u32 n_reg;
+ u32 user_reg;
+ u32 droop_reg;
+ u32 config_reg;
+ u32 status_reg;
+ u8 lock_bit;
+
+ u32 droop_val;
+ u32 config_val;
+ u32 user_val;
+ u32 user_vco_mask;
+ unsigned long low_vco_max_rate;
+
+ unsigned long min_rate;
+ unsigned long max_rate;
+};
+
+struct clk_hfpll {
+ struct hfpll_data const *d;
+ int init_done;
+
+ struct clk_regmap clkr;
+ spinlock_t lock;
+};
+
+#define to_clk_hfpll(_hw) \
+ container_of(to_clk_regmap(_hw), struct clk_hfpll, clkr)
+
+extern const struct clk_ops clk_ops_hfpll;
+
+#endif
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation
next prev parent reply other threads:[~2014-09-05 22:47 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-05 22:47 [PATCH v2 00/15] Krait clocks + Krait CPUfreq Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 01/15] clk: mux: Add unregistration API Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 02/15] clk: mux: Split out register accessors for reuse Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 03/15] clk: Add __clk_mux_determine_rate_closest Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 04/15] clk: divider: Make generic for usage elsewhere Stephen Boyd
2014-10-03 18:07 ` Stephen Boyd
2014-10-07 17:27 ` Srinivas Kandagatla
2014-10-07 18:26 ` Stephen Boyd
2014-10-07 19:28 ` Srinivas Kandagatla
2014-10-08 15:04 ` Srinivas Kandagatla
2014-09-05 22:47 ` Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 05/15] clk: Add safe switch hook Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 06/15] clk: Avoid sending high rates to downstream clocks during set_rate Stephen Boyd
2014-09-05 22:47 ` Stephen Boyd [this message]
2014-09-05 22:47 ` [PATCH v2 08/15] clk: qcom: Add HFPLL driver Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 09/15] clk: qcom: Add MSM8960/APQ8064's HFPLLs Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 10/15] clk: qcom: Add IPQ806X's HFPLLs Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 11/15] clk: qcom: Add support for Krait clocks Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 12/15] clk: qcom: Add KPSS ACC/GCC driver Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 13/15] clk: qcom: Add Krait clock controller driver Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 14/15] cpufreq: Add module to register cpufreq on Krait CPUs Stephen Boyd
2014-09-08 4:46 ` Viresh Kumar
2014-09-08 17:15 ` Christopher Covington
2014-09-09 0:37 ` Stephen Boyd
2014-09-09 4:53 ` Viresh Kumar
2014-09-05 22:47 ` Stephen Boyd
2014-09-05 22:47 ` [PATCH v2 15/15] ARM: dts: qcom: Add necessary DT data for Krait cpufreq Stephen Boyd
2014-09-08 9:42 ` [PATCH v2 00/15] Krait clocks + Krait CPUfreq Pramod Gurav
2014-09-08 11:59 ` Pramod Gurav
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=1409957256-23729-9-git-send-email-sboyd@codeaurora.org \
--to=sboyd@codeaurora.org \
--cc=linux-arm-kernel@lists.infradead.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).