From: Claudiu Beznea <claudiu.beznea@microchip.com>
To: <mturquette@baylibre.com>, <sboyd@kernel.org>,
<nicolas.ferre@microchip.com>, <alexandre.belloni@bootlin.com>,
<ludovic.desroches@microchip.com>
Cc: <bbrezillon@kernel.org>, <linux-kernel@vger.kernel.org>,
<linux-clk@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>,
"Claudiu Beznea" <claudiu.beznea@microchip.com>
Subject: [PATCH 13/19] clk: at91: clk-master: add master clock support for SAMA7G5
Date: Wed, 15 Jul 2020 14:24:21 +0300 [thread overview]
Message-ID: <1594812267-6697-14-git-send-email-claudiu.beznea@microchip.com> (raw)
In-Reply-To: <1594812267-6697-1-git-send-email-claudiu.beznea@microchip.com>
Add master clock support (MCK1..4) for SAMA7G5. SAMA7G5's PMC has
multiple master clocks feeding different subsystems. One of them
feeds image subsystem and is changeable based on image subsystem
needs.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
drivers/clk/at91/clk-master.c | 310 +++++++++++++++++++++++++++++++++++++++++-
drivers/clk/at91/pmc.h | 7 +
include/linux/clk/at91_pmc.h | 1 +
3 files changed, 313 insertions(+), 5 deletions(-)
diff --git a/drivers/clk/at91/clk-master.c b/drivers/clk/at91/clk-master.c
index 88d545b1698c..bd0d8a69a2cf 100644
--- a/drivers/clk/at91/clk-master.c
+++ b/drivers/clk/at91/clk-master.c
@@ -17,30 +17,49 @@
#define MASTER_DIV_SHIFT 8
#define MASTER_DIV_MASK 0x3
+#define PMC_MCR 0x30
+#define PMC_MCR_ID_MSK GENMASK(3, 0)
+#define PMC_MCR_CMD BIT(7)
+#define PMC_MCR_DIV GENMASK(10, 8)
+#define PMC_MCR_CSS GENMASK(20, 16)
+#define PMC_MCR_CSS_SHIFT (16)
+#define PMC_MCR_EN BIT(28)
+
+#define PMC_MCR_ID(x) ((x) & PMC_MCR_ID_MSK)
+
+#define MASTER_MAX_ID 4
+
#define to_clk_master(hw) container_of(hw, struct clk_master, hw)
struct clk_master {
struct clk_hw hw;
struct regmap *regmap;
+ spinlock_t *lock;
const struct clk_master_layout *layout;
const struct clk_master_characteristics *characteristics;
+ u32 *mux_table;
u32 mckr;
+ int chg_pid;
+ u8 id;
+ u8 parent;
+ u8 div;
};
-static inline bool clk_master_ready(struct regmap *regmap)
+static inline bool clk_master_ready(struct clk_master *master)
{
+ unsigned int bit = master->id ? AT91_PMC_MCKXRDY : AT91_PMC_MCKRDY;
unsigned int status;
- regmap_read(regmap, AT91_PMC_SR, &status);
+ regmap_read(master->regmap, AT91_PMC_SR, &status);
- return !!(status & AT91_PMC_MCKRDY);
+ return !!(status & bit);
}
static int clk_master_prepare(struct clk_hw *hw)
{
struct clk_master *master = to_clk_master(hw);
- while (!clk_master_ready(master->regmap))
+ while (!clk_master_ready(master))
cpu_relax();
return 0;
@@ -50,7 +69,7 @@ static int clk_master_is_prepared(struct clk_hw *hw)
{
struct clk_master *master = to_clk_master(hw);
- return clk_master_ready(master->regmap);
+ return clk_master_ready(master);
}
static unsigned long clk_master_recalc_rate(struct clk_hw *hw,
@@ -143,6 +162,287 @@ at91_clk_register_master(struct regmap *regmap,
return hw;
}
+static unsigned long
+clk_sama7g5_master_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_master *master = to_clk_master(hw);
+
+ return DIV_ROUND_CLOSEST_ULL(parent_rate, (1 << master->div));
+}
+
+static void clk_sama7g5_master_best_diff(struct clk_rate_request *req,
+ struct clk_hw *parent,
+ unsigned long parent_rate,
+ long *best_rate,
+ long *best_diff,
+ u32 div)
+{
+ unsigned long tmp_rate, tmp_diff;
+
+ if (div == MASTER_PRES_MAX)
+ tmp_rate = parent_rate / 3;
+ else
+ tmp_rate = parent_rate >> div;
+
+ tmp_diff = abs(req->rate - tmp_rate);
+
+ if (*best_diff < 0 || *best_diff >= tmp_diff) {
+ *best_rate = tmp_rate;
+ *best_diff = tmp_diff;
+ req->best_parent_rate = parent_rate;
+ req->best_parent_hw = parent;
+ }
+}
+
+static int clk_sama7g5_master_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct clk_master *master = to_clk_master(hw);
+ struct clk_rate_request req_parent = *req;
+ struct clk_hw *parent;
+ long best_rate = LONG_MIN, best_diff = LONG_MIN;
+ unsigned long parent_rate;
+ unsigned int div, i;
+
+ /* First: check the dividers of MCR. */
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+ parent = clk_hw_get_parent_by_index(hw, i);
+ if (!parent)
+ continue;
+
+ parent_rate = clk_hw_get_rate(parent);
+ if (!parent_rate)
+ continue;
+
+ for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
+ clk_sama7g5_master_best_diff(req, parent, parent_rate,
+ &best_rate, &best_diff,
+ div);
+ if (!best_diff)
+ break;
+ }
+
+ if (!best_diff)
+ break;
+ }
+
+ /* Second: try to request rate form changeable parent. */
+ if (master->chg_pid < 0)
+ goto end;
+
+ parent = clk_hw_get_parent_by_index(hw, master->chg_pid);
+ if (!parent)
+ goto end;
+
+ for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
+ if (div == MASTER_PRES_MAX)
+ req_parent.rate = req->rate * 3;
+ else
+ req_parent.rate = req->rate << div;
+
+ if (__clk_determine_rate(parent, &req_parent))
+ continue;
+
+ clk_sama7g5_master_best_diff(req, parent, req_parent.rate,
+ &best_rate, &best_diff, div);
+
+ if (!best_diff)
+ break;
+ }
+
+end:
+ pr_debug("MCK: %s, best_rate = %ld, parent clk: %s @ %ld\n",
+ __func__, best_rate,
+ __clk_get_name((req->best_parent_hw)->clk),
+ req->best_parent_rate);
+
+ if (best_rate < 0)
+ return -EINVAL;
+
+ req->rate = best_rate;
+
+ return 0;
+}
+
+static u8 clk_sama7g5_master_get_parent(struct clk_hw *hw)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long flags;
+ u8 index;
+
+ spin_lock_irqsave(master->lock, flags);
+ index = clk_mux_val_to_index(&master->hw, master->mux_table, 0,
+ master->parent);
+ spin_unlock_irqrestore(master->lock, flags);
+
+ return index;
+}
+
+static int clk_sama7g5_master_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long flags;
+
+ if (index >= clk_hw_get_num_parents(hw))
+ return -EINVAL;
+
+ spin_lock_irqsave(master->lock, flags);
+ master->parent = clk_mux_index_to_val(master->mux_table, 0, index);
+ spin_unlock_irqrestore(master->lock, flags);
+
+ return 0;
+}
+
+static int clk_sama7g5_master_enable(struct clk_hw *hw)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long flags;
+ unsigned int val, cparent;
+
+ spin_lock_irqsave(master->lock, flags);
+
+ regmap_write(master->regmap, PMC_MCR, PMC_MCR_ID(master->id));
+ regmap_read(master->regmap, PMC_MCR, &val);
+ regmap_update_bits(master->regmap, PMC_MCR,
+ PMC_MCR_EN | PMC_MCR_CSS | PMC_MCR_DIV |
+ PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ PMC_MCR_EN | (master->parent << PMC_MCR_CSS_SHIFT) |
+ (master->div << MASTER_DIV_SHIFT) |
+ PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+ cparent = (val & PMC_MCR_CSS) >> PMC_MCR_CSS_SHIFT;
+
+ /* Wait here only if parent is being changed. */
+ while ((cparent != master->parent) && !clk_master_ready(master))
+ cpu_relax();
+
+ spin_unlock_irqrestore(master->lock, flags);
+
+ return 0;
+}
+
+static void clk_sama7g5_master_disable(struct clk_hw *hw)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long flags;
+
+ spin_lock_irqsave(master->lock, flags);
+
+ regmap_write(master->regmap, PMC_MCR, master->id);
+ regmap_update_bits(master->regmap, PMC_MCR,
+ PMC_MCR_EN | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+ PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+ spin_unlock_irqrestore(master->lock, flags);
+}
+
+static int clk_sama7g5_master_is_enabled(struct clk_hw *hw)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long flags;
+ unsigned int val;
+
+ spin_lock_irqsave(master->lock, flags);
+
+ regmap_write(master->regmap, PMC_MCR, master->id);
+ regmap_read(master->regmap, PMC_MCR, &val);
+
+ spin_unlock_irqrestore(master->lock, flags);
+
+ return !!(val & PMC_MCR_EN);
+}
+
+static int clk_sama7g5_master_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_master *master = to_clk_master(hw);
+ unsigned long div, flags;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+ if ((div > (1 << (MASTER_PRES_MAX - 1))) || (div & (div - 1)))
+ return -EINVAL;
+
+ if (div == 3)
+ div = MASTER_PRES_MAX;
+ else
+ div = ffs(div) - 1;
+
+ spin_lock_irqsave(master->lock, flags);
+ master->div = div;
+ spin_unlock_irqrestore(master->lock, flags);
+
+ return 0;
+}
+
+static const struct clk_ops sama7g5_master_ops = {
+ .enable = clk_sama7g5_master_enable,
+ .disable = clk_sama7g5_master_disable,
+ .is_enabled = clk_sama7g5_master_is_enabled,
+ .recalc_rate = clk_sama7g5_master_recalc_rate,
+ .determine_rate = clk_sama7g5_master_determine_rate,
+ .set_rate = clk_sama7g5_master_set_rate,
+ .get_parent = clk_sama7g5_master_get_parent,
+ .set_parent = clk_sama7g5_master_set_parent,
+};
+
+struct clk_hw * __init
+at91_clk_sama7g5_register_master(struct regmap *regmap,
+ const char *name, int num_parents,
+ const char **parent_names,
+ u32 *mux_table,
+ spinlock_t *lock, u8 id,
+ bool critical, int chg_pid)
+{
+ struct clk_master *master;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ unsigned long flags;
+ unsigned int val;
+ int ret;
+
+ if (!name || !num_parents || !parent_names || !mux_table ||
+ !lock || id > MASTER_MAX_ID)
+ return ERR_PTR(-EINVAL);
+
+ master = kzalloc(sizeof(*master), GFP_KERNEL);
+ if (!master)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &sama7g5_master_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+ if (chg_pid >= 0)
+ init.flags |= CLK_SET_RATE_PARENT;
+ if (critical)
+ init.flags |= CLK_IS_CRITICAL;
+
+ master->hw.init = &init;
+ master->regmap = regmap;
+ master->id = id;
+ master->chg_pid = chg_pid;
+ master->lock = lock;
+ master->mux_table = mux_table;
+
+ spin_lock_irqsave(master->lock, flags);
+ regmap_write(master->regmap, PMC_MCR, master->id);
+ regmap_read(master->regmap, PMC_MCR, &val);
+ master->parent = (val & PMC_MCR_CSS) >> PMC_MCR_CSS_SHIFT;
+ master->div = (val & PMC_MCR_DIV) >> MASTER_DIV_SHIFT;
+ spin_unlock_irqrestore(master->lock, flags);
+
+ hw = &master->hw;
+ ret = clk_hw_register(NULL, &master->hw);
+ if (ret) {
+ kfree(master);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
const struct clk_master_layout at91rm9200_master_layout = {
.mask = 0x31F,
.pres_shift = 2,
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 2bfe1405f9f8..29d150feaa46 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -155,6 +155,13 @@ at91_clk_register_master(struct regmap *regmap, const char *name,
const struct clk_master_characteristics *characteristics);
struct clk_hw * __init
+at91_clk_sama7g5_register_master(struct regmap *regmap,
+ const char *name, int num_parents,
+ const char **parent_names, u32 *mux_table,
+ spinlock_t *lock, u8 id, bool critical,
+ int chg_pid);
+
+struct clk_hw * __init
at91_clk_register_peripheral(struct regmap *regmap, const char *name,
const char *parent_name, u32 id);
struct clk_hw * __init
diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
index 49a53a137610..77d6dabc4c3c 100644
--- a/include/linux/clk/at91_pmc.h
+++ b/include/linux/clk/at91_pmc.h
@@ -174,6 +174,7 @@
#define AT91_PMC_MOSCRCS (1 << 17) /* Main On-Chip RC [some SAM9] */
#define AT91_PMC_CFDEV (1 << 18) /* Clock Failure Detector Event [some SAM9] */
#define AT91_PMC_GCKRDY (1 << 24) /* Generated Clocks */
+#define AT91_PMC_MCKXRDY (1 << 26) /* Master Clock x [x=1..4] Ready Status */
#define AT91_PMC_IMR 0x6c /* Interrupt Mask Register */
#define AT91_PMC_FSMR 0x70 /* Fast Startup Mode Register */
--
2.7.4
next prev parent reply other threads:[~2020-07-15 11:25 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-15 11:24 [PATCH 00/19] clk: at91: add sama7g5 clock support Claudiu Beznea
2020-07-15 11:24 ` [PATCH 01/19] clk: at91: clk-generated: continue if __clk_determine_rate() returns error Claudiu Beznea
2020-07-17 9:09 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 02/19] clk: at91: clk-generated: check best_rate against ranges Claudiu Beznea
2020-07-17 9:10 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 03/19] clk: at91: clk-sam9x60-pll: fix mul mask Claudiu Beznea
2020-07-17 9:11 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 04/19] clk: at91: sam9x60-pll: use frac when computing pll frequency Claudiu Beznea
2020-07-15 11:24 ` [PATCH 05/19] clk: at91: sam9x60-pll: use logical or for range check Claudiu Beznea
2020-07-17 9:13 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 06/19] clk: at91: sam9x60-pll: check fcore against ranges Claudiu Beznea
2020-07-17 9:23 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 07/19] clk: at91: sam9x60-pll: use frac when setting frequency Claudiu Beznea
2020-07-17 9:12 ` Alexandre Belloni
2020-07-20 10:34 ` Claudiu.Beznea
2020-07-15 11:24 ` [PATCH 08/19] clk: at91: sam9x60: fix main rc oscillator frequency Claudiu Beznea
2020-07-17 9:17 ` Alexandre Belloni
2020-07-15 11:24 ` [PATCH 09/19] clk: at91: sckc: register slow_rc with accuracy option Claudiu Beznea
2020-07-15 15:39 ` Claudiu.Beznea
2020-07-15 11:24 ` [PATCH 10/19] clk: at91: replace conditional operator with double logical not Claudiu Beznea
2020-07-17 15:07 ` Alexandre Belloni
2020-07-20 10:36 ` Claudiu.Beznea
2020-07-15 11:24 ` [PATCH 11/19] clk: at91: clk-generated: pass the id of changeable parent at registration Claudiu Beznea
2020-07-16 16:57 ` Codrin.Ciubotariu
2020-07-15 11:24 ` [PATCH 12/19] clk: at91: clk-generated: add mux_table option Claudiu Beznea
2020-07-15 11:24 ` Claudiu Beznea [this message]
2020-07-15 11:24 ` [PATCH 14/19] clk: at91: clk-peripheral: add support for changeable parent rate Claudiu Beznea
2020-07-15 11:24 ` [PATCH 15/19] clk: at91: clk-programmable: add mux_table option Claudiu Beznea
2020-07-15 11:24 ` [PATCH 16/19] clk: at91: add macro for pll ids mask Claudiu Beznea
2020-07-15 11:24 ` [PATCH 17/19] clk: at91: clk-sam9x60-pll: re-factor to support plls with multiple outputs Claudiu Beznea
2020-07-15 11:24 ` [PATCH 18/19] clk: at91: clk-utmi: add utmi support for sama7g5 Claudiu Beznea
2020-07-15 11:24 ` [PATCH 19/19] clk: at91: sama7g5: add clock " Claudiu Beznea
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