Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1be3d053 authored by Colin Cross's avatar Colin Cross
Browse files

ARM: tegra: clock: prevent accidental disables of cpu clock 



Peripheral clocks that have no clock enable bit in the
enable registers have their clk_num set to 0.  Bit 0
in the clock enable registers is the CPU clock.
Prevent disables on these peripheral clocks from
accidentally disabling the CPU clock.

Signed-off-by: default avatarColin Cross <ccross@android.com>
Acked-by: default avatarOlof Johansson <olof@lixom.net>
parent 421186e7

arch/arm/mach-tegra/tegra2_clocks.c

+25 −0
Original line number Diff line number Diff line
@@ -946,9 +946,14 @@ static void tegra2_periph_clk_init(struct clk *c) 
	}



	c->state = ON;



	if (!c->u.periph.clk_num)

		return;



	if (!(clk_readl(CLK_OUT_ENB + PERIPH_CLK_TO_ENB_REG(c)) &

			PERIPH_CLK_TO_ENB_BIT(c)))

		c->state = OFF;



	if (!(c->flags & PERIPH_NO_RESET))

		if (clk_readl(RST_DEVICES + PERIPH_CLK_TO_ENB_REG(c)) &

				PERIPH_CLK_TO_ENB_BIT(c))
@@ -962,6 +967,9 @@ static int tegra2_periph_clk_enable(struct clk *c) 
	int refcount;

	pr_debug("%s on clock %s\n", __func__, c->name);



	if (!c->u.periph.clk_num)

		return 0;



	spin_lock_irqsave(&clock_register_lock, flags);



	refcount = tegra_periph_clk_enable_refcount[c->u.periph.clk_num]++;
@@ -994,6 +1002,9 @@ static void tegra2_periph_clk_disable(struct clk *c) 


	pr_debug("%s on clock %s\n", __func__, c->name);



	if (!c->u.periph.clk_num)

		return;



	spin_lock_irqsave(&clock_register_lock, flags);



	if (c->refcnt)
@@ -1012,6 +1023,9 @@ static void tegra2_periph_clk_reset(struct clk *c, bool assert) 


	pr_debug("%s %s on clock %s\n", __func__,

		 assert ? "assert" : "deassert", c->name);



	BUG_ON(!c->u.periph.clk_num);



	if (!(c->flags & PERIPH_NO_RESET))

		clk_writel(PERIPH_CLK_TO_ENB_BIT(c),

			   base + PERIPH_CLK_TO_ENB_SET_REG(c));
@@ -1182,6 +1196,10 @@ static void tegra2_clk_double_init(struct clk *c) 
	c->mul = 2;

	c->div = 1;

	c->state = ON;



	if (!c->u.periph.clk_num)

		return;



	if (!(clk_readl(CLK_OUT_ENB + PERIPH_CLK_TO_ENB_REG(c)) &

			PERIPH_CLK_TO_ENB_BIT(c)))

		c->state = OFF;
@@ -1269,6 +1287,9 @@ static void tegra2_cdev_clk_init(struct clk *c) 
	/* We could un-tristate the cdev1 or cdev2 pingroup here; this is

	 * currently done in the pinmux code. */

	c->state = ON;



	BUG_ON(!c->u.periph.clk_num);



	if (!(clk_readl(CLK_OUT_ENB + PERIPH_CLK_TO_ENB_REG(c)) &

			PERIPH_CLK_TO_ENB_BIT(c)))

		c->state = OFF;
@@ -1276,6 +1297,8 @@ static void tegra2_cdev_clk_init(struct clk *c) 


static int tegra2_cdev_clk_enable(struct clk *c)

{

	BUG_ON(!c->u.periph.clk_num);



	clk_writel(PERIPH_CLK_TO_ENB_BIT(c),

		CLK_OUT_ENB_SET + PERIPH_CLK_TO_ENB_SET_REG(c));

	return 0;
@@ -1283,6 +1306,8 @@ static int tegra2_cdev_clk_enable(struct clk *c) 


static void tegra2_cdev_clk_disable(struct clk *c)

{

	BUG_ON(!c->u.periph.clk_num);



	clk_writel(PERIPH_CLK_TO_ENB_BIT(c),

		CLK_OUT_ENB_CLR + PERIPH_CLK_TO_ENB_SET_REG(c));

}