clk: tegra: Refactor PLL programming code
Refactor the PLL programming code to make it useable by the new PLL types
introduced by Tegra114.
The following changes were done:
* Split programming the PLL into updating m,n,p and updating cpcon
* Move locking from _update_pll_cpcon() to clk_pll_set_rate()
* Introduce _get_pll_mnp() helper
* Move check for identical m,n,p values to clk_pll_set_rate()
* struct tegra_clk_pll_freq_table will always contain the values as defined
by the hardware.
* Simplify the arguments to clk_pll_wait_for_lock()
* Split _tegra_clk_register_pll()
Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 165f247..3feefb1 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (c) 2012, 2013, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
@@ -113,20 +113,28 @@
pll_writel_misc(val, pll);
}
-static int clk_pll_wait_for_lock(struct tegra_clk_pll *pll,
- void __iomem *lock_addr, u32 lock_bit_idx)
+static int clk_pll_wait_for_lock(struct tegra_clk_pll *pll)
{
int i;
- u32 val;
+ u32 val, lock_bit;
+ void __iomem *lock_addr;
if (!(pll->flags & TEGRA_PLL_USE_LOCK)) {
udelay(pll->params->lock_delay);
return 0;
}
+ lock_addr = pll->clk_base;
+ if (pll->flags & TEGRA_PLL_LOCK_MISC)
+ lock_addr += pll->params->misc_reg;
+ else
+ lock_addr += pll->params->base_reg;
+
+ lock_bit = BIT(pll->params->lock_bit_idx);
+
for (i = 0; i < pll->params->lock_delay; i++) {
val = readl_relaxed(lock_addr);
- if (val & BIT(lock_bit_idx)) {
+ if (val & lock_bit) {
udelay(PLL_POST_LOCK_DELAY);
return 0;
}
@@ -155,7 +163,7 @@
return val & PLL_BASE_ENABLE ? 1 : 0;
}
-static int _clk_pll_enable(struct clk_hw *hw)
+static void _clk_pll_enable(struct clk_hw *hw)
{
struct tegra_clk_pll *pll = to_clk_pll(hw);
u32 val;
@@ -172,11 +180,6 @@
val |= PMC_PLLP_WB0_OVERRIDE_PLLM_ENABLE;
writel_relaxed(val, pll->pmc + PMC_PLLP_WB0_OVERRIDE);
}
-
- clk_pll_wait_for_lock(pll, pll->clk_base + pll->params->base_reg,
- pll->params->lock_bit_idx);
-
- return 0;
}
static void _clk_pll_disable(struct clk_hw *hw)
@@ -204,7 +207,9 @@
if (pll->lock)
spin_lock_irqsave(pll->lock, flags);
- ret = _clk_pll_enable(hw);
+ _clk_pll_enable(hw);
+
+ ret = clk_pll_wait_for_lock(pll);
if (pll->lock)
spin_unlock_irqrestore(pll->lock, flags);
@@ -241,8 +246,6 @@
if (sel->input_rate == 0)
return -EINVAL;
- BUG_ON(sel->p < 1);
-
cfg->input_rate = sel->input_rate;
cfg->output_rate = sel->output_rate;
cfg->m = sel->m;
@@ -290,88 +293,109 @@
cfg->output_rate <<= 1)
p_div++;
- cfg->p = 1 << p_div;
+ cfg->p = p_div;
cfg->m = parent_rate / cfreq;
cfg->n = cfg->output_rate / cfreq;
cfg->cpcon = OUT_OF_TABLE_CPCON;
if (cfg->m > divm_max(pll) || cfg->n > divn_max(pll) ||
- cfg->p > divp_max(pll) || cfg->output_rate > pll->params->vco_max) {
+ (1 << p_div) > divp_max(pll)
+ || cfg->output_rate > pll->params->vco_max) {
pr_err("%s: Failed to set %s rate %lu\n",
__func__, __clk_get_name(hw->clk), rate);
return -EINVAL;
}
+ if (pll->flags & TEGRA_PLLU)
+ cfg->p ^= 1;
+
return 0;
}
+static void _update_pll_mnp(struct tegra_clk_pll *pll,
+ struct tegra_clk_pll_freq_table *cfg)
+{
+ u32 val;
+
+ val = pll_readl_base(pll);
+
+ val &= ~((divm_mask(pll) << pll->divm_shift) |
+ (divn_mask(pll) << pll->divn_shift) |
+ (divp_mask(pll) << pll->divp_shift));
+ val |= ((cfg->m << pll->divm_shift) |
+ (cfg->n << pll->divn_shift) |
+ (cfg->p << pll->divp_shift));
+
+ pll_writel_base(val, pll);
+}
+
+static void _get_pll_mnp(struct tegra_clk_pll *pll,
+ struct tegra_clk_pll_freq_table *cfg)
+{
+ u32 val;
+
+ val = pll_readl_base(pll);
+
+ cfg->m = (val >> pll->divm_shift) & (divm_mask(pll));
+ cfg->n = (val >> pll->divn_shift) & (divn_mask(pll));
+ cfg->p = (val >> pll->divp_shift) & (divp_mask(pll));
+}
+
+static void _update_pll_cpcon(struct tegra_clk_pll *pll,
+ struct tegra_clk_pll_freq_table *cfg,
+ unsigned long rate)
+{
+ u32 val;
+
+ val = pll_readl_misc(pll);
+
+ val &= ~(PLL_MISC_CPCON_MASK << PLL_MISC_CPCON_SHIFT);
+ val |= cfg->cpcon << PLL_MISC_CPCON_SHIFT;
+
+ if (pll->flags & TEGRA_PLL_SET_LFCON) {
+ val &= ~(PLL_MISC_LFCON_MASK << PLL_MISC_LFCON_SHIFT);
+ if (cfg->n >= PLLDU_LFCON_SET_DIVN)
+ val |= 1 << PLL_MISC_LFCON_SHIFT;
+ } else if (pll->flags & TEGRA_PLL_SET_DCCON) {
+ val &= ~(1 << PLL_MISC_DCCON_SHIFT);
+ if (rate >= (pll->params->vco_max >> 1))
+ val |= 1 << PLL_MISC_DCCON_SHIFT;
+ }
+
+ pll_writel_misc(val, pll);
+}
+
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);
- unsigned long flags = 0;
- u32 divp, val, old_base;
- int state;
-
- divp = __ffs(cfg->p);
-
- if (pll->flags & TEGRA_PLLU)
- divp ^= 1;
-
- if (pll->lock)
- spin_lock_irqsave(pll->lock, flags);
-
- old_base = val = pll_readl_base(pll);
- val &= ~((divm_mask(pll) << pll->divm_shift) |
- (divn_mask(pll) << pll->divn_shift) |
- (divp_mask(pll) << pll->divp_shift));
- val |= ((cfg->m << pll->divm_shift) |
- (cfg->n << pll->divn_shift) |
- (divp << pll->divp_shift));
- if (val == old_base) {
- if (pll->lock)
- spin_unlock_irqrestore(pll->lock, flags);
- return 0;
- }
+ int state, ret = 0;
state = clk_pll_is_enabled(hw);
- if (state) {
- _clk_pll_disable(hw);
- val &= ~(PLL_BASE_BYPASS | PLL_BASE_ENABLE);
- }
- pll_writel_base(val, pll);
-
- if (pll->flags & TEGRA_PLL_HAS_CPCON) {
- val = pll_readl_misc(pll);
- val &= ~(PLL_MISC_CPCON_MASK << PLL_MISC_CPCON_SHIFT);
- val |= cfg->cpcon << PLL_MISC_CPCON_SHIFT;
- if (pll->flags & TEGRA_PLL_SET_LFCON) {
- val &= ~(PLL_MISC_LFCON_MASK << PLL_MISC_LFCON_SHIFT);
- if (cfg->n >= PLLDU_LFCON_SET_DIVN)
- val |= 0x1 << PLL_MISC_LFCON_SHIFT;
- } else if (pll->flags & TEGRA_PLL_SET_DCCON) {
- val &= ~(0x1 << PLL_MISC_DCCON_SHIFT);
- if (rate >= (pll->params->vco_max >> 1))
- val |= 0x1 << PLL_MISC_DCCON_SHIFT;
- }
- pll_writel_misc(val, pll);
- }
-
- if (pll->lock)
- spin_unlock_irqrestore(pll->lock, flags);
-
if (state)
- clk_pll_enable(hw);
+ _clk_pll_disable(hw);
- return 0;
+ _update_pll_mnp(pll, cfg);
+
+ if (pll->flags & TEGRA_PLL_HAS_CPCON)
+ _update_pll_cpcon(pll, cfg, rate);
+
+ if (state) {
+ _clk_pll_enable(hw);
+ ret = clk_pll_wait_for_lock(pll);
+ }
+
+ return ret;
}
static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct tegra_clk_pll *pll = to_clk_pll(hw);
- struct tegra_clk_pll_freq_table cfg;
+ struct tegra_clk_pll_freq_table cfg, old_cfg;
+ unsigned long flags = 0;
+ int ret = 0;
if (pll->flags & TEGRA_PLL_FIXED) {
if (rate != pll->fixed_rate) {
@@ -387,7 +411,18 @@
_calc_rate(hw, &cfg, rate, parent_rate))
return -EINVAL;
- return _program_pll(hw, &cfg, rate);
+ if (pll->lock)
+ spin_lock_irqsave(pll->lock, flags);
+
+ _get_pll_mnp(pll, &old_cfg);
+
+ if (old_cfg.m != cfg.m || old_cfg.n != cfg.n || old_cfg.p != cfg.p)
+ ret = _program_pll(hw, &cfg, rate);
+
+ if (pll->lock)
+ spin_unlock_irqrestore(pll->lock, flags);
+
+ return ret;
}
static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
@@ -409,7 +444,7 @@
return -EINVAL;
output_rate *= cfg.n;
- do_div(output_rate, cfg.m * cfg.p);
+ do_div(output_rate, cfg.m * (1 << cfg.p));
return output_rate;
}
@@ -418,10 +453,12 @@
unsigned long parent_rate)
{
struct tegra_clk_pll *pll = to_clk_pll(hw);
- u32 val = pll_readl_base(pll);
- u32 divn = 0, divm = 0, divp = 0;
+ struct tegra_clk_pll_freq_table cfg;
+ u32 val;
u64 rate = parent_rate;
+ val = pll_readl_base(pll);
+
if (val & PLL_BASE_BYPASS)
return parent_rate;
@@ -435,16 +472,16 @@
return pll->fixed_rate;
}
- divp = (val >> pll->divp_shift) & (divp_mask(pll));
+ _get_pll_mnp(pll, &cfg);
+
if (pll->flags & TEGRA_PLLU)
- divp ^= 1;
+ cfg.p ^= 1;
- divn = (val >> pll->divn_shift) & (divn_mask(pll));
- divm = (val >> pll->divm_shift) & (divm_mask(pll));
- divm *= (1 << divp);
+ cfg.m *= 1 << cfg.p;
- rate *= divn;
- do_div(rate, divm);
+ rate *= cfg.n;
+ do_div(rate, cfg.m);
+
return rate;
}
@@ -538,8 +575,8 @@
val |= (PLL_BASE_BYPASS | PLL_BASE_ENABLE);
pll_writel_base(val, pll);
- clk_pll_wait_for_lock(pll, pll->clk_base + pll->params->misc_reg,
- pll->params->lock_bit_idx);
+ clk_pll_wait_for_lock(pll);
+
return 0;
}
@@ -577,28 +614,17 @@
.enable = clk_plle_enable,
};
-static struct clk *_tegra_clk_register_pll(const char *name,
- const char *parent_name, void __iomem *clk_base,
- void __iomem *pmc, unsigned long flags,
- unsigned long fixed_rate,
- struct tegra_clk_pll_params *pll_params, u8 pll_flags,
- struct tegra_clk_pll_freq_table *freq_table, spinlock_t *lock,
- const struct clk_ops *ops)
+static struct tegra_clk_pll *_tegra_init_pll(void __iomem *clk_base,
+ void __iomem *pmc, unsigned long fixed_rate,
+ struct tegra_clk_pll_params *pll_params, u32 pll_flags,
+ struct tegra_clk_pll_freq_table *freq_table, spinlock_t *lock)
{
struct tegra_clk_pll *pll;
- struct clk *clk;
- struct clk_init_data init;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
- init.name = name;
- init.ops = ops;
- init.flags = flags;
- init.parent_names = (parent_name ? &parent_name : NULL);
- init.num_parents = (parent_name ? 1 : 0);
-
pll->clk_base = clk_base;
pll->pmc = pmc;
@@ -615,34 +641,68 @@
pll->divm_shift = PLL_BASE_DIVM_SHIFT;
pll->divm_width = PLL_BASE_DIVM_WIDTH;
+ return pll;
+}
+
+static struct clk *_tegra_clk_register_pll(struct tegra_clk_pll *pll,
+ const char *name, const char *parent_name, unsigned long flags,
+ const struct clk_ops *ops)
+{
+ struct clk_init_data init;
+
+ init.name = name;
+ init.ops = ops;
+ init.flags = flags;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
/* Data in .init is copied by clk_register(), so stack variable OK */
pll->hw.init = &init;
- clk = clk_register(NULL, &pll->hw);
+ return clk_register(NULL, &pll->hw);
+}
+
+struct clk *tegra_clk_register_pll(const char *name, const char *parent_name,
+ void __iomem *clk_base, void __iomem *pmc,
+ unsigned long flags, unsigned long fixed_rate,
+ struct tegra_clk_pll_params *pll_params, u32 pll_flags,
+ struct tegra_clk_pll_freq_table *freq_table, spinlock_t *lock)
+{
+ struct tegra_clk_pll *pll;
+ struct clk *clk;
+
+ pll = _tegra_init_pll(clk_base, pmc, fixed_rate, pll_params, pll_flags,
+ freq_table, lock);
+ if (IS_ERR(pll))
+ return ERR_CAST(pll);
+
+ clk = _tegra_clk_register_pll(pll, name, parent_name, flags,
+ &tegra_clk_pll_ops);
if (IS_ERR(clk))
kfree(pll);
return clk;
}
-struct clk *tegra_clk_register_pll(const char *name, const char *parent_name,
- void __iomem *clk_base, void __iomem *pmc,
- unsigned long flags, unsigned long fixed_rate,
- struct tegra_clk_pll_params *pll_params, u8 pll_flags,
- struct tegra_clk_pll_freq_table *freq_table, spinlock_t *lock)
-{
- return _tegra_clk_register_pll(name, parent_name, clk_base, pmc,
- flags, fixed_rate, pll_params, pll_flags, freq_table,
- lock, &tegra_clk_pll_ops);
-}
-
struct clk *tegra_clk_register_plle(const char *name, const char *parent_name,
void __iomem *clk_base, void __iomem *pmc,
unsigned long flags, unsigned long fixed_rate,
- struct tegra_clk_pll_params *pll_params, u8 pll_flags,
+ struct tegra_clk_pll_params *pll_params, u32 pll_flags,
struct tegra_clk_pll_freq_table *freq_table, spinlock_t *lock)
{
- return _tegra_clk_register_pll(name, parent_name, clk_base, pmc,
- flags, fixed_rate, pll_params, pll_flags, freq_table,
- lock, &tegra_clk_plle_ops);
+ struct tegra_clk_pll *pll;
+ struct clk *clk;
+ pll_flags |= TEGRA_PLL_LOCK_MISC;
+
+ pll = _tegra_init_pll(clk_base, pmc, fixed_rate, pll_params, pll_flags,
+ freq_table, lock);
+ if (IS_ERR(pll))
+ return ERR_CAST(pll);
+
+ clk = _tegra_clk_register_pll(pll, name, parent_name, flags,
+ &tegra_clk_plle_ops);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
}