/*
* Slewing plls should be bought up at frequency which is in the middle of the
* desired VCO range. So after bringing up the pll at calibration freq, set it
* back to desired frequency(that was set by previous clk_set_rate).
*/
static int __calibrate_alpha_pll(struct alpha_pll_clk *pll)
{
unsigned long calibration_freq, freq_hz;
struct alpha_pll_vco_tbl *vco_tbl = pll->vco_tbl;
u64 a_val;
u32 l_val, vco_val;
int rc;
vco_val = find_vco(pll, pll->c.rate);
if (IS_ERR_VALUE(vco_val)) {
pr_err("alpha pll: not in a valid vco range\n");
return -EINVAL;
}
/*
* As during slewing plls vco_sel won't be allowed to change, vco table
* should have only one entry table, i.e. index = 0, find the
* calibration frequency.
*/
calibration_freq = (vco_tbl[0].min_freq +
vco_tbl[0].max_freq)/2;
freq_hz = round_rate_up(pll, calibration_freq, &l_val, &a_val);
if (freq_hz != calibration_freq) {
pr_err("alpha_pll: call clk_set_rate with rounded rates!\n");
return -EINVAL;
}
setup_alpha_pll_values(a_val, l_val, vco_tbl->vco_val, pll);
/* Bringup the pll at calibration frequency */
rc = __alpha_pll_enable(pll, false);
if (rc) {
pr_err("alpha pll calibration failed\n");
return rc;
}
/*
* PLL is already running at calibration frequency.
* So slew pll to the previously set frequency.
*/
pr_debug("pll %s: setting back to required rate %lu\n", pll->c.dbg_name,
pll->c.rate);
freq_hz = round_rate_up(pll, pll->c.rate, &l_val, &a_val);
setup_alpha_pll_values(a_val, l_val, UINT_MAX, pll);
dyna_alpha_pll_dynamic_update(pll);
return 0;
}
static int fabia_alpha_pll_set_rate(struct clk *c, unsigned long rate)
{
struct alpha_pll_clk *pll = to_alpha_pll_clk(c);
unsigned long flags, freq_hz;
u32 l_val;
u64 a_val;
freq_hz = round_rate_up(pll, rate, &l_val, &a_val);
if (freq_hz > rate + FABIA_RATE_MARGIN || freq_hz < rate) {
pr_err("%s: Call clk_set_rate with rounded rates!\n",
c->dbg_name);
return -EINVAL;
}
spin_lock_irqsave(&c->lock, flags);
/* Set the new L value */
writel_relaxed(l_val, FABIA_L_REG(pll));
if (pll->fabia_frac_offset)
writel_relaxed(a_val, FABIA_FRAC_OFF(pll));
else
writel_relaxed(a_val, FABIA_FRAC_REG(pll));
alpha_pll_dynamic_update(pll);
spin_unlock_irqrestore(&c->lock, flags);
return 0;
}
static long alpha_pll_round_rate(struct clk *c, unsigned long rate)
{
struct alpha_pll_clk *pll = to_alpha_pll_clk(c);
struct alpha_pll_vco_tbl *v = pll->vco_tbl;
int ret;
u32 l_val;
unsigned long freq_hz;
u64 a_val;
int i;
if (pll->no_prepared_reconfig && c->prepare_count)
return -EINVAL;
freq_hz = round_rate_up(pll, rate, &l_val, &a_val);
if (rate < pll->min_supported_freq)
return pll->min_supported_freq;
if (pll->is_fabia)
return freq_hz;
ret = find_vco(pll, freq_hz);
if (!IS_ERR_VALUE(ret))
return freq_hz;
freq_hz = 0;
for (i = 0; i < pll->num_vco; i++) {
if (is_better_rate(rate, freq_hz, v[i].min_freq))
freq_hz = v[i].min_freq;
if (is_better_rate(rate, freq_hz, v[i].max_freq))
freq_hz = v[i].max_freq;
}
if (!freq_hz)
return -EINVAL;
return freq_hz;
}
static int alpha_pll_set_rate(struct clk *c, unsigned long rate)
{
struct alpha_pll_clk *pll = to_alpha_pll_clk(c);
struct alpha_pll_masks *masks = pll->masks;
unsigned long flags, freq_hz;
u32 regval, l_val;
int vco_val;
u64 a_val;
freq_hz = round_rate_up(pll, rate, &l_val, &a_val);
if (freq_hz != rate) {
pr_err("alpha_pll: Call clk_set_rate with rounded rates!\n");
return -EINVAL;
}
vco_val = find_vco(pll, freq_hz);
if (IS_ERR_VALUE(vco_val)) {
pr_err("alpha pll: not in a valid vco range\n");
return -EINVAL;
}
/*
* Ensure PLL is off before changing rate. For optimization reasons,
* assume no downstream clock is actively using it. No support
* for dynamic update at the moment.
*/
spin_lock_irqsave(&c->lock, flags);
if (c->count)
alpha_pll_disable(c);
a_val = a_val << (ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH);
writel_relaxed(l_val, L_REG(pll));
__iowrite32_copy(A_REG(pll), &a_val, 2);
if (masks->vco_mask) {
regval = readl_relaxed(VCO_REG(pll));
regval &= ~(masks->vco_mask << masks->vco_shift);
regval |= vco_val << masks->vco_shift;
writel_relaxed(regval, VCO_REG(pll));
}
regval = readl_relaxed(ALPHA_EN_REG(pll));
regval |= masks->alpha_en_mask;
writel_relaxed(regval, ALPHA_EN_REG(pll));
if (c->count)
alpha_pll_enable(c);
spin_unlock_irqrestore(&c->lock, flags);
return 0;
}
static void update_vco_tbl(struct alpha_pll_clk *pll)
{
int i, l_val;
u64 a_val;
unsigned long hz;
/* Round vco limits to valid rates */
for (i = 0; i < pll->num_vco; i++) {
hz = round_rate_up(pll, pll->vco_tbl[i].min_freq, &l_val,
&a_val);
pll->vco_tbl[i].min_freq = hz;
hz = round_rate_down(pll, pll->vco_tbl[i].max_freq, &l_val,
&a_val);
pll->vco_tbl[i].max_freq = hz;
}
}
static int dyna_alpha_pll_set_rate(struct clk *c, unsigned long rate)
{
struct alpha_pll_clk *pll = to_alpha_pll_clk(c);
unsigned long freq_hz, flags;
u32 l_val, vco_val;
u64 a_val;
int ret;
freq_hz = round_rate_up(pll, rate, &l_val, &a_val);
if (freq_hz != rate) {
pr_err("alpha_pll: Call clk_set_rate with rounded rates!\n");
return -EINVAL;
}
vco_val = find_vco(pll, freq_hz);
/*
* Dynamic pll update will not support switching frequencies across
* vco ranges. In those cases fall back to normal alpha set rate.
*/
if (pll->current_vco_val != vco_val) {
ret = alpha_pll_set_rate(c, rate);
if (!ret)
pll->current_vco_val = vco_val;
else
return ret;
return 0;
}
spin_lock_irqsave(&c->lock, flags);
a_val = a_val << (ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH);
writel_relaxed(l_val, L_REG(pll));
__iowrite32_copy(A_REG(pll), &a_val, 2);
/* Ensure that the write above goes through before proceeding. */
mb();
if (c->count)
dyna_alpha_pll_dynamic_update(pll);
spin_unlock_irqrestore(&c->lock, flags);
return 0;
}
