Commit 7968d241 authored by Jon Mason's avatar Jon Mason Committed by Stephen Boyd
Browse files

clk: iproc: Add PLL base write function 



All writes to the PLL base address must be flushed if the
IPROC_CLK_NEEDS_READ_BACK flag is set.  If we add a function to make the
necessary write and reads, we can make sure that any future code which
makes PLL base writes will do the correct thing.

Signed-off-by: default avatarJon Mason <jonmason@broadcom.com>
Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
parent 5f024b06

drivers/clk/bcm/clk-iproc-pll.c

+33 −47
Original line number Diff line number Diff line
@@ -137,6 +137,18 @@ static int pll_wait_for_lock(struct iproc_pll *pll) 
	return -EIO;

}



static void iproc_pll_write(const struct iproc_pll *pll, void __iomem *base,

			    const u32 offset, u32 val)

{

	const struct iproc_pll_ctrl *ctrl = pll->ctrl;



	writel(val, base + offset);



	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK &&

		     base == pll->pll_base))

		val = readl(base + offset);

}



static void __pll_disable(struct iproc_pll *pll)

{

	const struct iproc_pll_ctrl *ctrl = pll->ctrl;
@@ -145,27 +157,24 @@ static void __pll_disable(struct iproc_pll *pll) 
	if (ctrl->flags & IPROC_CLK_PLL_ASIU) {

		val = readl(pll->asiu_base + ctrl->asiu.offset);

		val &= ~(1 << ctrl->asiu.en_shift);

		writel(val, pll->asiu_base + ctrl->asiu.offset);

		iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);

	}



	if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {

		val = readl(pll->pll_base + ctrl->aon.offset);

		val |= bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift;

		writel(val, pll->pll_base + ctrl->aon.offset);



		if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

			readl(pll->pll_base + ctrl->aon.offset);

		iproc_pll_write(pll, pll->pll_base, ctrl->aon.offset, val);

	}



	if (pll->pwr_base) {

		/* latch input value so core power can be shut down */

		val = readl(pll->pwr_base + ctrl->aon.offset);

		val |= 1 << ctrl->aon.iso_shift;

		writel(val, pll->pwr_base + ctrl->aon.offset);

		iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);



		/* power down the core */

		val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);

		writel(val, pll->pwr_base + ctrl->aon.offset);

		iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);

	}

}
@@ -177,10 +186,7 @@ static int __pll_enable(struct iproc_pll *pll) 
	if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {

		val = readl(pll->pll_base + ctrl->aon.offset);

		val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);

		writel(val, pll->pll_base + ctrl->aon.offset);



		if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

			readl(pll->pll_base + ctrl->aon.offset);

		iproc_pll_write(pll, pll->pll_base, ctrl->aon.offset, val);

	}



	if (pll->pwr_base) {
@@ -188,14 +194,14 @@ static int __pll_enable(struct iproc_pll *pll) 
		val = readl(pll->pwr_base + ctrl->aon.offset);

		val |= bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift;

		val &= ~(1 << ctrl->aon.iso_shift);

		writel(val, pll->pwr_base + ctrl->aon.offset);

		iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);

	}



	/* certain PLLs also need to be ungated from the ASIU top level */

	if (ctrl->flags & IPROC_CLK_PLL_ASIU) {

		val = readl(pll->asiu_base + ctrl->asiu.offset);

		val |= (1 << ctrl->asiu.en_shift);

		writel(val, pll->asiu_base + ctrl->asiu.offset);

		iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);

	}



	return 0;
@@ -209,9 +215,7 @@ static void __pll_put_in_reset(struct iproc_pll *pll) 


	val = readl(pll->pll_base + reset->offset);

	val &= ~(1 << reset->reset_shift | 1 << reset->p_reset_shift);

	writel(val, pll->pll_base + reset->offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + reset->offset);

	iproc_pll_write(pll, pll->pll_base, reset->offset, val);

}



static void __pll_bring_out_reset(struct iproc_pll *pll, unsigned int kp,
@@ -228,9 +232,7 @@ static void __pll_bring_out_reset(struct iproc_pll *pll, unsigned int kp, 
	val |=  ki << reset->ki_shift | kp << reset->kp_shift |

		ka << reset->ka_shift;

	val |= 1 << reset->reset_shift | 1 << reset->p_reset_shift;

	writel(val, pll->pll_base + reset->offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + reset->offset);

	iproc_pll_write(pll, pll->pll_base, reset->offset, val);

}



static int pll_set_rate(struct iproc_clk *clk, unsigned int rate_index,
@@ -285,9 +287,8 @@ static int pll_set_rate(struct iproc_clk *clk, unsigned int rate_index, 
	/* put PLL in reset */

	__pll_put_in_reset(pll);



	writel(0, pll->pll_base + ctrl->vco_ctrl.u_offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->vco_ctrl.u_offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->vco_ctrl.u_offset, 0);



	val = readl(pll->pll_base + ctrl->vco_ctrl.l_offset);



	if (rate >= VCO_LOW && rate < VCO_MID)
@@ -298,17 +299,13 @@ static int pll_set_rate(struct iproc_clk *clk, unsigned int rate_index, 
	else

		val |= (1 << PLL_VCO_HIGH_SHIFT);



	writel(val, pll->pll_base + ctrl->vco_ctrl.l_offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->vco_ctrl.l_offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->vco_ctrl.l_offset, val);



	/* program integer part of NDIV */

	val = readl(pll->pll_base + ctrl->ndiv_int.offset);

	val &= ~(bit_mask(ctrl->ndiv_int.width) << ctrl->ndiv_int.shift);

	val |= vco->ndiv_int << ctrl->ndiv_int.shift;

	writel(val, pll->pll_base + ctrl->ndiv_int.offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->ndiv_int.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->ndiv_int.offset, val);



	/* program fractional part of NDIV */

	if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
@@ -316,18 +313,15 @@ static int pll_set_rate(struct iproc_clk *clk, unsigned int rate_index, 
		val &= ~(bit_mask(ctrl->ndiv_frac.width) <<

			 ctrl->ndiv_frac.shift);

		val |= vco->ndiv_frac << ctrl->ndiv_frac.shift;

		writel(val, pll->pll_base + ctrl->ndiv_frac.offset);

		if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

			readl(pll->pll_base + ctrl->ndiv_frac.offset);

		iproc_pll_write(pll, pll->pll_base, ctrl->ndiv_frac.offset,

				val);

	}



	/* program PDIV */

	val = readl(pll->pll_base + ctrl->pdiv.offset);

	val &= ~(bit_mask(ctrl->pdiv.width) << ctrl->pdiv.shift);

	val |= vco->pdiv << ctrl->pdiv.shift;

	writel(val, pll->pll_base + ctrl->pdiv.offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->pdiv.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->pdiv.offset, val);



	__pll_bring_out_reset(pll, kp, ka, ki);
@@ -467,14 +461,12 @@ static int iproc_clk_enable(struct clk_hw *hw) 
	/* channel enable is active low */

	val = readl(pll->pll_base + ctrl->enable.offset);

	val &= ~(1 << ctrl->enable.enable_shift);

	writel(val, pll->pll_base + ctrl->enable.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);



	/* also make sure channel is not held */

	val = readl(pll->pll_base + ctrl->enable.offset);

	val &= ~(1 << ctrl->enable.hold_shift);

	writel(val, pll->pll_base + ctrl->enable.offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->enable.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);



	return 0;

}
@@ -491,9 +483,7 @@ static void iproc_clk_disable(struct clk_hw *hw) 


	val = readl(pll->pll_base + ctrl->enable.offset);

	val |= 1 << ctrl->enable.enable_shift;

	writel(val, pll->pll_base + ctrl->enable.offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->enable.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);

}



static unsigned long iproc_clk_recalc_rate(struct clk_hw *hw,
@@ -562,9 +552,7 @@ static int iproc_clk_set_rate(struct clk_hw *hw, unsigned long rate, 
		val &= ~(bit_mask(ctrl->mdiv.width) << ctrl->mdiv.shift);

		val |= div << ctrl->mdiv.shift;

	}

	writel(val, pll->pll_base + ctrl->mdiv.offset);

	if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

		readl(pll->pll_base + ctrl->mdiv.offset);

	iproc_pll_write(pll, pll->pll_base, ctrl->mdiv.offset, val);

	clk->rate = parent_rate / div;



	return 0;
@@ -591,9 +579,7 @@ static void iproc_pll_sw_cfg(struct iproc_pll *pll) 


		val = readl(pll->pll_base + ctrl->sw_ctrl.offset);

		val |= BIT(ctrl->sw_ctrl.shift);

		writel(val, pll->pll_base + ctrl->sw_ctrl.offset);

		if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))

			readl(pll->pll_base + ctrl->sw_ctrl.offset);

		iproc_pll_write(pll, pll->pll_base, ctrl->sw_ctrl.offset, val);

	}

}

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