Commit 63cc5a4d authored by Thierry Reding's avatar Thierry Reding
Browse files

clk: tegra: Model oscillator as clock 



Currently the Tegra clock driver simplifies the clock tree somewhat by
taking advantage of the fact that clk_m runs at the same frequency as
the oscillator. While that's true on all currently supported SoCs, it
does not apply to Tegra210 anymore. On Tegra210 clk_m is typically
divided down from the oscillator frequency. To support that setup, add
a separate clock for the oscillator that both clk_m and pll_ref derive
from.

Modify the tegra_osc_clk_init() function to take an additional divider
parameter for clk_m. Existing SoCs always pass in 1, whereas Tegra210
will read the divider from a register in the clock & reset controller.

Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent 699b477a

drivers/clk/tegra/clk-tegra-fixed.c

+13 −11
Original line number Diff line number Diff line
@@ -30,13 +30,12 @@ 
#define OSC_CTRL_OSC_FREQ_SHIFT		28

#define OSC_CTRL_PLL_REF_DIV_SHIFT	26



int __init tegra_osc_clk_init(void __iomem *clk_base,

				struct tegra_clk *tegra_clks,

				unsigned long *input_freqs, int num,

				unsigned long *osc_freq,

int __init tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *clks,

			      unsigned long *input_freqs, unsigned int num,

			      unsigned int clk_m_div, unsigned long *osc_freq,

			      unsigned long *pll_ref_freq)

{

	struct clk *clk;

	struct clk *clk, *osc;

	struct clk **dt_clk;

	u32 val, pll_ref_div;

	unsigned osc_idx;
@@ -54,22 +53,25 @@ int __init tegra_osc_clk_init(void __iomem *clk_base, 
		return -EINVAL;

	}



	dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m, tegra_clks);

	osc = clk_register_fixed_rate(NULL, "osc", NULL, CLK_IS_ROOT,

				      *osc_freq);



	dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m, clks);

	if (!dt_clk)

		return 0;



	clk = clk_register_fixed_rate(NULL, "clk_m", NULL, CLK_IS_ROOT,

				      *osc_freq);

	clk = clk_register_fixed_factor(NULL, "clk_m", "osc",

					0, 1, clk_m_div);

	*dt_clk = clk;



	/* pll_ref */

	val = (val >> OSC_CTRL_PLL_REF_DIV_SHIFT) & 3;

	pll_ref_div = 1 << val;

	dt_clk = tegra_lookup_dt_id(tegra_clk_pll_ref, tegra_clks);

	dt_clk = tegra_lookup_dt_id(tegra_clk_pll_ref, clks);

	if (!dt_clk)

		return 0;



	clk = clk_register_fixed_factor(NULL, "pll_ref", "clk_m",

	clk = clk_register_fixed_factor(NULL, "pll_ref", "osc",

					0, 1, pll_ref_div);

	*dt_clk = clk;

drivers/clk/tegra/clk-tegra124.c

+2 −1
Original line number Diff line number Diff line
@@ -1480,7 +1480,8 @@ static void __init tegra124_132_clock_init_pre(struct device_node *np) 
		return;



	if (tegra_osc_clk_init(clk_base, tegra124_clks, tegra124_input_freq,

		ARRAY_SIZE(tegra124_input_freq), &osc_freq, &pll_ref_freq) < 0)

			       ARRAY_SIZE(tegra124_input_freq), 1, &osc_freq,

			       &pll_ref_freq) < 0)

		return;



	tegra_fixed_clk_init(tegra124_clks);

drivers/clk/tegra/clk-tegra30.c

+2 −1
Original line number Diff line number Diff line
@@ -1434,7 +1434,8 @@ static void __init tegra30_clock_init(struct device_node *np) 
		return;



	if (tegra_osc_clk_init(clk_base, tegra30_clks, tegra30_input_freq,

		ARRAY_SIZE(tegra30_input_freq), &input_freq, NULL) < 0)

			       ARRAY_SIZE(tegra30_input_freq), 1, &input_freq,

			       NULL) < 0)

		return;

drivers/clk/tegra/clk.h

+4 −4
Original line number Diff line number Diff line
@@ -615,9 +615,9 @@ void tegra_periph_clk_init(void __iomem *clk_base, void __iomem *pmc_base, 


void tegra_pmc_clk_init(void __iomem *pmc_base, struct tegra_clk *tegra_clks);

void tegra_fixed_clk_init(struct tegra_clk *tegra_clks);

int tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *tegra_clks,

				unsigned long *input_freqs, int num,

				unsigned long *osc_freq,

int tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *clks,

		       unsigned long *input_freqs, unsigned int num,

		       unsigned int clk_m_div, unsigned long *osc_freq,

		       unsigned long *pll_ref_freq);

void tegra_super_clk_gen4_init(void __iomem *clk_base,

			void __iomem *pmc_base, struct tegra_clk *tegra_clks,

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