Commit 83ce0357 authored by Gabriel Fernandez's avatar Gabriel Fernandez Committed by Stephen Boyd
Browse files

clk: stm32mp13: add safe mux management 



Some muxes need to set a the safe position when clock is off.

Signed-off-by: default avatarGabriel Fernandez <gabriel.fernandez@foss.st.com>
Link: https://lore.kernel.org/r/20220516070600.7692-12-gabriel.fernandez@foss.st.com


Signed-off-by: default avatarStephen Boyd <sboyd@kernel.org>
parent ffa2d04d

drivers/clk/stm32/clk-stm32-core.c

+54 −0
Original line number Diff line number Diff line
@@ -495,6 +495,54 @@ static int clk_stm32_composite_is_enabled(struct clk_hw *hw) 
	return stm32_gate_is_enabled(composite->base, composite->clock_data, composite->gate_id);

}



#define MUX_SAFE_POSITION 0



static int clk_stm32_has_safe_mux(struct clk_hw *hw)

{

	struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);

	const struct stm32_mux_cfg *mux = &composite->clock_data->muxes[composite->mux_id];



	return !!(mux->flags & MUX_SAFE);

}



static void clk_stm32_set_safe_position_mux(struct clk_hw *hw)

{

	struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);



	if (!clk_stm32_composite_is_enabled(hw)) {

		unsigned long flags = 0;



		if (composite->clock_data->is_multi_mux) {

			struct clk_hw *other_mux_hw = NULL;



			other_mux_hw = composite->clock_data->is_multi_mux(hw);



			if (!other_mux_hw || clk_stm32_composite_is_enabled(other_mux_hw))

				return;

		}



		spin_lock_irqsave(composite->lock, flags);



		stm32_mux_set_parent(composite->base, composite->clock_data,

				     composite->mux_id, MUX_SAFE_POSITION);



		spin_unlock_irqrestore(composite->lock, flags);

	}

}



static void clk_stm32_safe_restore_position_mux(struct clk_hw *hw)

{

	struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);

	int sel = clk_hw_get_parent_index(hw);

	unsigned long flags = 0;



	spin_lock_irqsave(composite->lock, flags);



	stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, sel);



	spin_unlock_irqrestore(composite->lock, flags);

}



static void clk_stm32_composite_gate_endisable(struct clk_hw *hw, int enable)

{

	struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
@@ -516,6 +564,9 @@ static int clk_stm32_composite_gate_enable(struct clk_hw *hw) 


	clk_stm32_composite_gate_endisable(hw, 1);



	if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))

		clk_stm32_safe_restore_position_mux(hw);



	return 0;

}
@@ -527,6 +578,9 @@ static void clk_stm32_composite_gate_disable(struct clk_hw *hw) 
		return;



	clk_stm32_composite_gate_endisable(hw, 0);



	if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))

		clk_stm32_set_safe_position_mux(hw);

}



static void clk_stm32_composite_disable_unused(struct clk_hw *hw)

drivers/clk/stm32/clk-stm32-core.h

+1 −0
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ int stm32_rcc_init(struct device *dev, const struct of_device_id *match_data, 


/* MUX define */

#define MUX_NO_RDY		0xFF

#define MUX_SAFE		BIT(7)



/* DIV define */

#define DIV_NO_RDY		0xFF

drivers/clk/stm32/clk-stm32mp13.c

+7 −4
Original line number Diff line number Diff line
@@ -359,6 +359,9 @@ enum enum_mux_cfg { 
#define CFG_MUX(_id, _offset, _shift, _witdh)\

	_CFG_MUX(_id, _offset, _shift, _witdh, MUX_NO_RDY, 0)



#define CFG_MUX_SAFE(_id, _offset, _shift, _witdh)\

	_CFG_MUX(_id, _offset, _shift, _witdh, MUX_NO_RDY, MUX_SAFE)



static const struct stm32_mux_cfg stm32mp13_muxes[] = {

	CFG_MUX(MUX_I2C12,	RCC_I2C12CKSELR,	0, 3),

	CFG_MUX(MUX_LPTIM45,	RCC_LPTIM45CKSELR,	0, 3),
@@ -394,10 +397,10 @@ static const struct stm32_mux_cfg stm32mp13_muxes[] = { 
	CFG_MUX(MUX_UART6,	RCC_UART6CKSELR,	0, 3),

	CFG_MUX(MUX_USBO,	RCC_USBCKSELR,		4, 1),

	CFG_MUX(MUX_USBPHY,	RCC_USBCKSELR,		0, 2),

	CFG_MUX(MUX_FMC,	RCC_FMCCKSELR,		0, 2),

	CFG_MUX(MUX_QSPI,	RCC_QSPICKSELR,		0, 2),

	CFG_MUX(MUX_SDMMC1,	RCC_SDMMC12CKSELR,	0, 3),

	CFG_MUX(MUX_SDMMC2,	RCC_SDMMC12CKSELR,	3, 3),

	CFG_MUX_SAFE(MUX_FMC,	RCC_FMCCKSELR,		0, 2),

	CFG_MUX_SAFE(MUX_QSPI,	RCC_QSPICKSELR,		0, 2),

	CFG_MUX_SAFE(MUX_SDMMC1, RCC_SDMMC12CKSELR,	0, 3),

	CFG_MUX_SAFE(MUX_SDMMC2, RCC_SDMMC12CKSELR,	3, 3),

};



struct clk_stm32_securiy {