248 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			248 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Marvell PXA family clocks
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|  *
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|  * Copyright (C) 2014 Robert Jarzmik
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|  *
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|  * Common clock code for PXA clocks ("CKEN" type clocks + DT)
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation; version 2 of the License.
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|  *
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|  */
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| #include <linux/clk.h>
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| #include <linux/clk-provider.h>
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| #include <linux/clkdev.h>
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| #include <linux/of.h>
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| 
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| #include <dt-bindings/clock/pxa-clock.h>
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| #include "clk-pxa.h"
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| 
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| #define KHz 1000
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| #define MHz (1000 * 1000)
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| 
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| #define MDREFR_K0DB4	(1 << 29)	/* SDCLK0 Divide by 4 Control/Status */
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| #define MDREFR_K2FREE	(1 << 25)	/* SDRAM Free-Running Control */
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| #define MDREFR_K1FREE	(1 << 24)	/* SDRAM Free-Running Control */
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| #define MDREFR_K0FREE	(1 << 23)	/* SDRAM Free-Running Control */
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| #define MDREFR_SLFRSH	(1 << 22)	/* SDRAM Self-Refresh Control/Status */
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| #define MDREFR_APD	(1 << 20)	/* SDRAM/SSRAM Auto-Power-Down Enable */
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| #define MDREFR_K2DB2	(1 << 19)	/* SDCLK2 Divide by 2 Control/Status */
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| #define MDREFR_K2RUN	(1 << 18)	/* SDCLK2 Run Control/Status */
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| #define MDREFR_K1DB2	(1 << 17)	/* SDCLK1 Divide by 2 Control/Status */
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| #define MDREFR_K1RUN	(1 << 16)	/* SDCLK1 Run Control/Status */
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| #define MDREFR_E1PIN	(1 << 15)	/* SDCKE1 Level Control/Status */
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| #define MDREFR_K0DB2	(1 << 14)	/* SDCLK0 Divide by 2 Control/Status */
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| #define MDREFR_K0RUN	(1 << 13)	/* SDCLK0 Run Control/Status */
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| #define MDREFR_E0PIN	(1 << 12)	/* SDCKE0 Level Control/Status */
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| #define MDREFR_DB2_MASK	(MDREFR_K2DB2 | MDREFR_K1DB2)
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| #define MDREFR_DRI_MASK	0xFFF
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| 
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| static DEFINE_SPINLOCK(pxa_clk_lock);
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| 
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| static struct clk *pxa_clocks[CLK_MAX];
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| static struct clk_onecell_data onecell_data = {
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| 	.clks = pxa_clocks,
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| 	.clk_num = CLK_MAX,
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| };
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| 
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| struct pxa_clk {
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| 	struct clk_hw hw;
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| 	struct clk_fixed_factor lp;
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| 	struct clk_fixed_factor hp;
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| 	struct clk_gate gate;
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| 	bool (*is_in_low_power)(void);
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| };
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| 
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| #define to_pxa_clk(_hw) container_of(_hw, struct pxa_clk, hw)
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| 
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| static unsigned long cken_recalc_rate(struct clk_hw *hw,
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| 				      unsigned long parent_rate)
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| {
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| 	struct pxa_clk *pclk = to_pxa_clk(hw);
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| 	struct clk_fixed_factor *fix;
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| 
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| 	if (!pclk->is_in_low_power || pclk->is_in_low_power())
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| 		fix = &pclk->lp;
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| 	else
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| 		fix = &pclk->hp;
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| 	__clk_hw_set_clk(&fix->hw, hw);
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| 	return clk_fixed_factor_ops.recalc_rate(&fix->hw, parent_rate);
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| }
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| 
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| static struct clk_ops cken_rate_ops = {
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| 	.recalc_rate = cken_recalc_rate,
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| };
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| 
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| static u8 cken_get_parent(struct clk_hw *hw)
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| {
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| 	struct pxa_clk *pclk = to_pxa_clk(hw);
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| 
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| 	if (!pclk->is_in_low_power)
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| 		return 0;
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| 	return pclk->is_in_low_power() ? 0 : 1;
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| }
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| 
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| static struct clk_ops cken_mux_ops = {
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| 	.get_parent = cken_get_parent,
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| 	.set_parent = dummy_clk_set_parent,
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| };
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| 
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| void __init clkdev_pxa_register(int ckid, const char *con_id,
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| 				const char *dev_id, struct clk *clk)
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| {
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| 	if (!IS_ERR(clk) && (ckid != CLK_NONE))
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| 		pxa_clocks[ckid] = clk;
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| 	if (!IS_ERR(clk))
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| 		clk_register_clkdev(clk, con_id, dev_id);
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| }
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| 
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| int __init clk_pxa_cken_init(const struct desc_clk_cken *clks, int nb_clks)
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| {
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| 	int i;
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| 	struct pxa_clk *pxa_clk;
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| 	struct clk *clk;
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| 
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| 	for (i = 0; i < nb_clks; i++) {
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| 		pxa_clk = kzalloc(sizeof(*pxa_clk), GFP_KERNEL);
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| 		pxa_clk->is_in_low_power = clks[i].is_in_low_power;
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| 		pxa_clk->lp = clks[i].lp;
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| 		pxa_clk->hp = clks[i].hp;
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| 		pxa_clk->gate = clks[i].gate;
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| 		pxa_clk->gate.lock = &pxa_clk_lock;
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| 		clk = clk_register_composite(NULL, clks[i].name,
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| 					     clks[i].parent_names, 2,
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| 					     &pxa_clk->hw, &cken_mux_ops,
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| 					     &pxa_clk->hw, &cken_rate_ops,
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| 					     &pxa_clk->gate.hw, &clk_gate_ops,
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| 					     clks[i].flags);
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| 		clkdev_pxa_register(clks[i].ckid, clks[i].con_id,
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| 				    clks[i].dev_id, clk);
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| 	}
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| 	return 0;
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| }
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| 
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| void __init clk_pxa_dt_common_init(struct device_node *np)
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| {
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| 	of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data);
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| }
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| 
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| void pxa2xx_core_turbo_switch(bool on)
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| {
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| 	unsigned long flags;
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| 	unsigned int unused, clkcfg;
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| 
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| 	local_irq_save(flags);
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| 
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| 	asm("mrc p14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
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| 	clkcfg &= ~CLKCFG_TURBO & ~CLKCFG_HALFTURBO;
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| 	if (on)
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| 		clkcfg |= CLKCFG_TURBO;
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| 	clkcfg |= CLKCFG_FCS;
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| 
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| 	asm volatile(
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| 	"	b	2f\n"
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| 	"	.align	5\n"
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| 	"1:	mcr	p14, 0, %1, c6, c0, 0\n"
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| 	"	b	3f\n"
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| 	"2:	b	1b\n"
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| 	"3:	nop\n"
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| 		: "=&r" (unused) : "r" (clkcfg));
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| 
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| 	local_irq_restore(flags);
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| }
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| 
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| void pxa2xx_cpll_change(struct pxa2xx_freq *freq,
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| 			u32 (*mdrefr_dri)(unsigned int), void __iomem *mdrefr,
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| 			void __iomem *cccr)
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| {
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| 	unsigned int clkcfg = freq->clkcfg;
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| 	unsigned int unused, preset_mdrefr, postset_mdrefr;
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 
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| 	/* Calculate the next MDREFR.  If we're slowing down the SDRAM clock
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| 	 * we need to preset the smaller DRI before the change.	 If we're
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| 	 * speeding up we need to set the larger DRI value after the change.
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| 	 */
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| 	preset_mdrefr = postset_mdrefr = readl(mdrefr);
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| 	if ((preset_mdrefr & MDREFR_DRI_MASK) > mdrefr_dri(freq->membus_khz)) {
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| 		preset_mdrefr = (preset_mdrefr & ~MDREFR_DRI_MASK);
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| 		preset_mdrefr |= mdrefr_dri(freq->membus_khz);
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| 	}
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| 	postset_mdrefr =
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| 		(postset_mdrefr & ~MDREFR_DRI_MASK) |
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| 		mdrefr_dri(freq->membus_khz);
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| 
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| 	/* If we're dividing the memory clock by two for the SDRAM clock, this
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| 	 * must be set prior to the change.  Clearing the divide must be done
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| 	 * after the change.
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| 	 */
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| 	if (freq->div2) {
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| 		preset_mdrefr  |= MDREFR_DB2_MASK;
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| 		postset_mdrefr |= MDREFR_DB2_MASK;
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| 	} else {
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| 		postset_mdrefr &= ~MDREFR_DB2_MASK;
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| 	}
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| 
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| 	/* Set new the CCCR and prepare CLKCFG */
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| 	writel(freq->cccr, cccr);
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| 
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| 	asm volatile(
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| 	"	ldr	r4, [%1]\n"
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| 	"	b	2f\n"
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| 	"	.align	5\n"
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| 	"1:	str	%3, [%1]		/* preset the MDREFR */\n"
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| 	"	mcr	p14, 0, %2, c6, c0, 0	/* set CLKCFG[FCS] */\n"
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| 	"	str	%4, [%1]		/* postset the MDREFR */\n"
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| 	"	b	3f\n"
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| 	"2:	b	1b\n"
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| 	"3:	nop\n"
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| 	     : "=&r" (unused)
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| 	     : "r" (mdrefr), "r" (clkcfg), "r" (preset_mdrefr),
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| 	       "r" (postset_mdrefr)
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| 	     : "r4", "r5");
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| 
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| 	local_irq_restore(flags);
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| }
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| 
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| int pxa2xx_determine_rate(struct clk_rate_request *req,
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| 			  struct pxa2xx_freq *freqs, int nb_freqs)
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| {
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| 	int i, closest_below = -1, closest_above = -1;
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| 	unsigned long rate;
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| 
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| 	for (i = 0; i < nb_freqs; i++) {
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| 		rate = freqs[i].cpll;
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| 		if (rate == req->rate)
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| 			break;
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| 		if (rate < req->min_rate)
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| 			continue;
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| 		if (rate > req->max_rate)
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| 			continue;
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| 		if (rate <= req->rate)
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| 			closest_below = i;
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| 		if ((rate >= req->rate) && (closest_above == -1))
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| 			closest_above = i;
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| 	}
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| 
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| 	req->best_parent_hw = NULL;
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| 
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| 	if (i < nb_freqs) {
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| 		rate = req->rate;
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| 	} else if (closest_below >= 0) {
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| 		rate = freqs[closest_below].cpll;
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| 	} else if (closest_above >= 0) {
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| 		rate = freqs[closest_above].cpll;
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| 	} else {
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| 		pr_debug("%s(rate=%lu) no match\n", __func__, req->rate);
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| 		return -EINVAL;
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| 	}
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| 
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| 	pr_debug("%s(rate=%lu) rate=%lu\n", __func__, req->rate, rate);
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| 	req->rate = rate;
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| 
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| 	return 0;
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| }
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