[PATCH v4 16/20] clk: tegra: pll: Add Set_default logic

From: Rhyland Klein
Date: Mon May 04 2015 - 12:40:17 EST


From: Bill Huang <bilhuang@xxxxxxxxxx>

Add logic which (if specified for a pll) can verify that a PLL is set
to the proper default value and if not can set it. This can be
specified per PLL as each will have different default values.

Based on original work by Aleksandr Frid <afrid@xxxxxxxxxx>

Signed-off-by: Bill Huang <bilhuang@xxxxxxxxxx>
---
v2:
- Remove MACRO for PLL_MISC_CHECK_DEFAULT as suggested, and instead
the tegra210 driver will include an inline version of this function.

drivers/clk/tegra/clk-pll.c | 46 ++++++++++++++++++++++++++++++++-----------
drivers/clk/tegra/clk.h | 2 ++
2 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 94416018e35c..778f2de0045e 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -658,15 +658,28 @@ static int _program_pll(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
unsigned long rate)
{
struct tegra_clk_pll *pll = to_clk_pll(hw);
+ struct tegra_clk_pll_freq_table old_cfg;
int state, ret = 0;

state = clk_pll_is_enabled(hw);

+ _get_pll_mnp(pll, &old_cfg);
+
+ if (state && pll->params->defaults_set && pll->params->dyn_ramp &&
+ (cfg->m == old_cfg.m) && (cfg->p == old_cfg.p)) {
+ ret = pll->params->dyn_ramp(pll, cfg);
+ if (!ret)
+ return 0;
+ }
+
if (state) {
pll_clk_stop_ss(pll);
_clk_pll_disable(hw);
}

+ if (!pll->params->defaults_set && pll->params->set_defaults)
+ pll->params->set_defaults(pll);
+
_update_pll_mnp(pll, cfg);

if (pll->params->flags & TEGRA_PLL_HAS_CPCON)
@@ -1526,6 +1539,9 @@ static struct clk *_tegra_clk_register_pll(struct tegra_clk_pll *pll,
if (!pll->params->calc_rate)
pll->params->calc_rate = _calc_rate;

+ if (pll->params->set_defaults)
+ pll->params->set_defaults(pll);
+
/* Data in .init is copied by clk_register(), so stack variable OK */
pll->hw.init = &init;

@@ -1644,7 +1660,6 @@ struct clk *tegra_clk_register_pllxc(const char *name, const char *parent_name,
struct tegra_clk_pll *pll;
struct clk *clk, *parent;
unsigned long parent_rate;
- int err;
u32 val, val_iddq;

parent = __clk_lookup(parent_name);
@@ -1665,18 +1680,27 @@ struct clk *tegra_clk_register_pllxc(const char *name, const char *parent_name,
pll_params->vco_min = pll_params->adjust_vco(pll_params,
parent_rate);

- err = _setup_dynamic_ramp(pll_params, clk_base, parent_rate);
- if (err)
- return ERR_PTR(err);
+ /*
+ * If the pll has a set_defaults callback, it will take care of
+ * configuring dynamic ramping and setting IDDQ in that path.
+ */
+ if (!pll_params->set_defaults) {
+ int err;

- val = readl_relaxed(clk_base + pll_params->base_reg);
- val_iddq = readl_relaxed(clk_base + pll_params->iddq_reg);
+ err = _setup_dynamic_ramp(pll_params, clk_base, parent_rate);
+ if (err)
+ return ERR_PTR(err);

- if (val & PLL_BASE_ENABLE)
- WARN_ON(val_iddq & BIT(pll_params->iddq_bit_idx));
- else {
- val_iddq |= BIT(pll_params->iddq_bit_idx);
- writel_relaxed(val_iddq, clk_base + pll_params->iddq_reg);
+ val = readl_relaxed(clk_base + pll_params->base_reg);
+ val_iddq = readl_relaxed(clk_base + pll_params->iddq_reg);
+
+ if (val & PLL_BASE_ENABLE)
+ WARN_ON(val_iddq & BIT(pll_params->iddq_bit_idx));
+ else {
+ val_iddq |= BIT(pll_params->iddq_bit_idx);
+ writel_relaxed(val_iddq,
+ clk_base + pll_params->iddq_reg);
+ }
}

pll = _tegra_init_pll(clk_base, pmc, pll_params, lock);
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 74cf6242a57a..c111a89bb5ea 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -239,6 +239,7 @@ struct tegra_clk_pll_params {
int stepb_shift;
int lock_delay;
int max_p;
+ bool defaults_set;
struct pdiv_map *pdiv_tohw;
struct div_nmp *div_nmp;
struct tegra_clk_pll_freq_table *freq_table;
@@ -254,6 +255,7 @@ struct tegra_clk_pll_params {
unsigned long parent_rate);
int (*dyn_ramp)(struct tegra_clk_pll *pll,
struct tegra_clk_pll_freq_table *cfg);
+ void (*set_defaults)(struct tegra_clk_pll *pll);
};

#define TEGRA_PLL_USE_LOCK BIT(0)
--
1.7.9.5

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