[RESEND PATCH 3/5] clk: samsung: Add set_rate() clk_ops for PLL35xx
Vikas Sajjan
vikas.sajjan at linaro.org
Fri May 24 06:31:16 EDT 2013
From: Yadwinder Singh Brar <yadi.brar at samsung.com>
Adds set_rate() and round_rate() clk_ops for PLL35xx
The round_rate() implemenation as of now is dummy, it returns the same rate
which is passed as input.
Signed-off-by: Yadwinder Singh Brar <yadi.brar at samsung.com>
---
drivers/clk/samsung/clk-pll.c | 95 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 94 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index b8c0260..291cc9e 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -11,6 +11,7 @@
#include <linux/errno.h>
#include <linux/sort.h>
+#include <linux/bsearch.h>
#include "clk.h"
#include "clk-pll.h"
@@ -36,6 +37,21 @@ static int samsung_compare_rate(const void *_a, const void *_b)
return a->rate - b->rate;
}
+static struct samsung_pll_rate_table *samsung_get_pll_settings(
+ struct samsung_clk_pll *pll, unsigned long rate)
+{
+ struct samsung_pll_rate_table req_rate, *tmp;
+
+ req_rate.rate = rate;
+ tmp = bsearch(&req_rate, pll->rate_table, pll->rate_count,
+ sizeof(struct samsung_pll_rate_table),
+ samsung_compare_rate);
+ if (tmp)
+ return tmp;
+
+ return NULL;
+}
+
/*
* PLL35xx Clock Type
*/
@@ -46,9 +62,15 @@ static int samsung_compare_rate(const void *_a, const void *_b)
#define PLL35XX_MDIV_MASK (0x3FF)
#define PLL35XX_PDIV_MASK (0x3F)
#define PLL35XX_SDIV_MASK (0x7)
+#define PLL35XX_LOCK_STAT_MASK (0x1)
#define PLL35XX_MDIV_SHIFT (16)
#define PLL35XX_PDIV_SHIFT (8)
#define PLL35XX_SDIV_SHIFT (0)
+#define PLL35XX_LOCK_STAT_SHIFT (29)
+
+#define PLL35XX_MDIV(_tmp) ((_tmp) & (PLL35XX_MDIV_MASK << PLL35XX_MDIV_SHIFT))
+#define PLL35XX_PDIV(_tmp) ((_tmp) & (PLL35XX_PDIV_MASK << PLL35XX_PDIV_SHIFT))
+#define PLL35XX_SDIV(_tmp) ((_tmp) & (PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT))
static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
@@ -68,8 +90,76 @@ static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw,
return (unsigned long)fvco;
}
-static const struct clk_ops samsung_pll35xx_clk_ops = {
+static inline bool samsung_pll35xx_mp_change(u32 mdiv, u32 pdiv, u32 pll_con)
+{
+ if ((mdiv != PLL35XX_MDIV(pll_con)) || (pdiv != PLL35XX_PDIV(pll_con)))
+ return 1;
+ else
+ return 0;
+}
+
+static int samsung_pll35xx_set_rate(struct clk_hw *hw, unsigned long drate,
+ unsigned long prate)
+{
+ struct samsung_clk_pll *pll = to_clk_pll(hw);
+ struct samsung_pll_rate_table *rate;
+
+ u32 tmp, mdiv, pdiv, sdiv;
+
+ /* Get required rate settings from table */
+ rate = samsung_get_pll_settings(pll, drate);
+ if (!rate) {
+ pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
+ drate, __clk_get_name(hw->clk));
+ return -EINVAL;
+ }
+
+ mdiv = PLL35XX_MDIV(rate->pll_con0);
+ pdiv = PLL35XX_PDIV(rate->pll_con0);
+ sdiv = PLL35XX_SDIV(rate->pll_con0);
+
+ tmp = pll_readl(pll, PLL35XX_CON0_OFFSET);
+
+ if (!(samsung_pll35xx_mp_change(mdiv, pdiv, tmp))) {
+ /* If only s change, change just s value only*/
+ tmp &= ~(PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT);
+ tmp |= sdiv;
+ pll_writel(pll, tmp, PLL35XX_CON0_OFFSET);
+ } else {
+ /* Set PLL lock time.
+ Maximum lock time can be 270 * PDIV cycles */
+ pll_writel(pll, (pdiv >> PLL35XX_PDIV_SHIFT) * 270,
+ PLL35XX_LOCK_OFFSET);
+
+ /* Change PLL PMS values */
+ tmp &= ~((PLL35XX_MDIV_MASK << PLL35XX_MDIV_SHIFT) |
+ (PLL35XX_PDIV_MASK << PLL35XX_PDIV_SHIFT) |
+ (PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT));
+ tmp |= mdiv | pdiv | sdiv;
+ pll_writel(pll, tmp, PLL35XX_CON0_OFFSET);
+
+ /* wait_lock_time */
+ do {
+ cpu_relax();
+ tmp = pll_readl(pll, PLL35XX_CON0_OFFSET);
+ } while (!(tmp & (PLL35XX_LOCK_STAT_MASK
+ << PLL35XX_LOCK_STAT_SHIFT)));
+ }
+
+ return 0;
+}
+
+static long samsung_pll35xx_round_rate(struct clk_hw *hw,
+ unsigned long drate, unsigned long *prate)
+{
+ /* Clock framework cries without this, so implemented dummy */
+ return drate;
+}
+
+static struct clk_ops samsung_pll35xx_clk_ops = {
.recalc_rate = samsung_pll35xx_recalc_rate,
+ .round_rate = samsung_pll35xx_round_rate,
+ .set_rate = samsung_pll35xx_set_rate,
};
struct clk * __init samsung_clk_register_pll35xx(const char *name,
@@ -102,6 +192,9 @@ struct clk * __init samsung_clk_register_pll35xx(const char *name,
sort(pll->rate_table, pll->rate_count,
sizeof(struct samsung_pll_rate_table),
samsung_compare_rate, NULL);
+ } else {
+ samsung_pll35xx_clk_ops.round_rate = NULL;
+ samsung_pll35xx_clk_ops.set_rate = NULL;
}
clk = clk_register(NULL, &pll->hw);
--
1.7.9.5
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