[PATCH v6 14/25] clk: tegra: pll: Add support for PLLMB for T210

From: Rhyland Klein
Date: Thu Jun 18 2015 - 17:34:21 EST


Tegra210 SoC's have 2 PLLS for memory usage. Add plumbing to register
and handle PLLMB.

PLLMB is used to allow switching between 2 PLLM's without having to use
and intermediate backup PLL, as we need to lock the PLL before we can
switch to it.

Reviewed-by: Benson Leung <bleung@xxxxxxxxxxxx>
Signed-off-by: Rhyland Klein <rklein@xxxxxxxxxx>
---
v3:
- Flushed out comment more.

v2:
- Fixed commit description as suggested.

drivers/clk/tegra/clk-pll.c | 42 ++++++++++++++++++++++++++++++++++++++++--
drivers/clk/tegra/clk.h | 9 +++++++++
2 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index e63f16268c16..1f70c356bdd7 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -562,7 +562,7 @@ static void _update_pll_mnp(struct tegra_clk_pll *pll,
struct tegra_clk_pll_params *params = pll->params;
struct div_nmp *div_nmp = params->div_nmp;

- if ((params->flags & TEGRA_PLLM) &&
+ if ((params->flags & (TEGRA_PLLM | TEGRA_PLLMB)) &&
(pll_override_readl(PMC_PLLP_WB0_OVERRIDE, pll) &
PMC_PLLP_WB0_OVERRIDE_PLLM_OVERRIDE)) {
val = pll_override_readl(params->pmc_divp_reg, pll);
@@ -599,7 +599,7 @@ static void _get_pll_mnp(struct tegra_clk_pll *pll,
struct tegra_clk_pll_params *params = pll->params;
struct div_nmp *div_nmp = params->div_nmp;

- if ((params->flags & TEGRA_PLLM) &&
+ if ((params->flags & (TEGRA_PLLM | TEGRA_PLLMB)) &&
(pll_override_readl(PMC_PLLP_WB0_OVERRIDE, pll) &
PMC_PLLP_WB0_OVERRIDE_PLLM_OVERRIDE)) {
val = pll_override_readl(params->pmc_divp_reg, pll);
@@ -2235,4 +2235,42 @@ struct clk *tegra_clk_register_pllss_tegra210(const char *name,

return clk;
}
+
+struct clk *tegra_clk_register_pllmb(const char *name, const char *parent_name,
+ void __iomem *clk_base, void __iomem *pmc,
+ unsigned long flags,
+ struct tegra_clk_pll_params *pll_params,
+ spinlock_t *lock)
+{
+ struct tegra_clk_pll *pll;
+ struct clk *clk, *parent;
+ unsigned long parent_rate;
+
+ if (!pll_params->pdiv_tohw)
+ return ERR_PTR(-EINVAL);
+
+ parent = __clk_lookup(parent_name);
+ if (!parent) {
+ WARN(1, "parent clk %s of %s must be registered first\n",
+ parent_name, name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ parent_rate = __clk_get_rate(parent);
+
+ pll_params->vco_min = _clip_vco_min(pll_params->vco_min, parent_rate);
+
+ pll_params->flags |= TEGRA_PLL_BYPASS;
+ pll_params->flags |= TEGRA_PLLMB;
+ pll = _tegra_init_pll(clk_base, pmc, pll_params, 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;
+}
#endif
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 211c3463deba..6170fcef7c33 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -225,6 +225,8 @@ struct div_nmp {
* TEGRA_PLL_HAS_LOCK_ENABLE - PLL has bit to enable lock monitoring
* TEGRA_MDIV_NEW - Switch to new method for calculating fixed mdiv
* it may be more accurate (especially if SDM present)
+ * TEGRA_PLLMB - PLLMB has should be treated similar to PLLM. This
+ * flag indicated that it is PLLMB.
*/
struct tegra_clk_pll_params {
unsigned long input_min;
@@ -281,6 +283,7 @@ struct tegra_clk_pll_params {
#define TEGRA_PLL_BYPASS BIT(9)
#define TEGRA_PLL_HAS_LOCK_ENABLE BIT(10)
#define TEGRA_MDIV_NEW BIT(11)
+#define TEGRA_PLLMB BIT(12)

/**
* struct tegra_clk_pll - Tegra PLL clock
@@ -387,6 +390,12 @@ struct clk *tegra_clk_register_pllss(const char *name, const char *parent_name,
struct tegra_clk_pll_params *pll_params,
spinlock_t *lock);

+struct clk *tegra_clk_register_pllmb(const char *name, const char *parent_name,
+ void __iomem *clk_base, void __iomem *pmc,
+ unsigned long flags,
+ struct tegra_clk_pll_params *pll_params,
+ spinlock_t *lock);
+
/**
* struct tegra_clk_pll_out - PLL divider down clock
*
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/