alistair23-linux/arch/arm/mach-omap2/dpll3xxx.c

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/*
* OMAP3/4 - specific DPLL control functions
*
* Copyright (C) 2009-2010 Texas Instruments, Inc.
* Copyright (C) 2009-2010 Nokia Corporation
*
* Written by Paul Walmsley
* Testing and integration fixes by Jouni Högander
*
* 36xx support added by Vishwanath BS, Richard Woodruff, and Nishanth
* Menon
*
* Parts of this code are based on code written by
* Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/bitops.h>
#include <linux/clkdev.h>
#include "clockdomain.h"
#include "clock.h"
/* CM_AUTOIDLE_PLL*.AUTO_* bit values */
#define DPLL_AUTOIDLE_DISABLE 0x0
#define DPLL_AUTOIDLE_LOW_POWER_STOP 0x1
#define MAX_DPLL_WAIT_TRIES 1000000
/* Private functions */
/* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
static void _omap3_dpll_write_clken(struct clk_hw_omap *clk, u8 clken_bits)
{
const struct dpll_data *dd;
u32 v;
dd = clk->dpll_data;
v = omap2_clk_readl(clk, dd->control_reg);
v &= ~dd->enable_mask;
v |= clken_bits << __ffs(dd->enable_mask);
omap2_clk_writel(v, clk, dd->control_reg);
}
/* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
static int _omap3_wait_dpll_status(struct clk_hw_omap *clk, u8 state)
{
const struct dpll_data *dd;
int i = 0;
int ret = -EINVAL;
const char *clk_name;
dd = clk->dpll_data;
clk_name = __clk_get_name(clk->hw.clk);
state <<= __ffs(dd->idlest_mask);
while (((omap2_clk_readl(clk, dd->idlest_reg) & dd->idlest_mask)
!= state) && i < MAX_DPLL_WAIT_TRIES) {
i++;
udelay(1);
}
if (i == MAX_DPLL_WAIT_TRIES) {
printk(KERN_ERR "clock: %s failed transition to '%s'\n",
clk_name, (state) ? "locked" : "bypassed");
} else {
pr_debug("clock: %s transition to '%s' in %d loops\n",
clk_name, (state) ? "locked" : "bypassed", i);
ret = 0;
}
return ret;
}
/* From 3430 TRM ES2 4.7.6.2 */
static u16 _omap3_dpll_compute_freqsel(struct clk_hw_omap *clk, u8 n)
{
unsigned long fint;
u16 f = 0;
fint = __clk_get_rate(clk->dpll_data->clk_ref) / n;
pr_debug("clock: fint is %lu\n", fint);
if (fint >= 750000 && fint <= 1000000)
f = 0x3;
else if (fint > 1000000 && fint <= 1250000)
f = 0x4;
else if (fint > 1250000 && fint <= 1500000)
f = 0x5;
else if (fint > 1500000 && fint <= 1750000)
f = 0x6;
else if (fint > 1750000 && fint <= 2100000)
f = 0x7;
else if (fint > 7500000 && fint <= 10000000)
f = 0xB;
else if (fint > 10000000 && fint <= 12500000)
f = 0xC;
else if (fint > 12500000 && fint <= 15000000)
f = 0xD;
else if (fint > 15000000 && fint <= 17500000)
f = 0xE;
else if (fint > 17500000 && fint <= 21000000)
f = 0xF;
else
pr_debug("clock: unknown freqsel setting for %d\n", n);
return f;
}
/*
* _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
* @clk: pointer to a DPLL struct clk
*
* Instructs a non-CORE DPLL to lock. Waits for the DPLL to report
* readiness before returning. Will save and restore the DPLL's
* autoidle state across the enable, per the CDP code. If the DPLL
* locked successfully, return 0; if the DPLL did not lock in the time
* allotted, or DPLL3 was passed in, return -EINVAL.
*/
static int _omap3_noncore_dpll_lock(struct clk_hw_omap *clk)
{
const struct dpll_data *dd;
u8 ai;
u8 state = 1;
int r = 0;
pr_debug("clock: locking DPLL %s\n", __clk_get_name(clk->hw.clk));
dd = clk->dpll_data;
state <<= __ffs(dd->idlest_mask);
/* Check if already locked */
if ((omap2_clk_readl(clk, dd->idlest_reg) & dd->idlest_mask) == state)
goto done;
ai = omap3_dpll_autoidle_read(clk);
if (ai)
omap3_dpll_deny_idle(clk);
_omap3_dpll_write_clken(clk, DPLL_LOCKED);
r = _omap3_wait_dpll_status(clk, 1);
if (ai)
omap3_dpll_allow_idle(clk);
done:
return r;
}
/*
* _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
* @clk: pointer to a DPLL struct clk
*
* Instructs a non-CORE DPLL to enter low-power bypass mode. In
* bypass mode, the DPLL's rate is set equal to its parent clock's
* rate. Waits for the DPLL to report readiness before returning.
* Will save and restore the DPLL's autoidle state across the enable,
* per the CDP code. If the DPLL entered bypass mode successfully,
* return 0; if the DPLL did not enter bypass in the time allotted, or
* DPLL3 was passed in, or the DPLL does not support low-power bypass,
* return -EINVAL.
*/
static int _omap3_noncore_dpll_bypass(struct clk_hw_omap *clk)
{
int r;
u8 ai;
if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
return -EINVAL;
pr_debug("clock: configuring DPLL %s for low-power bypass\n",
__clk_get_name(clk->hw.clk));
ai = omap3_dpll_autoidle_read(clk);
_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);
r = _omap3_wait_dpll_status(clk, 0);
if (ai)
omap3_dpll_allow_idle(clk);
return r;
}
/*
* _omap3_noncore_dpll_stop - instruct a DPLL to stop
* @clk: pointer to a DPLL struct clk
*
* Instructs a non-CORE DPLL to enter low-power stop. Will save and
* restore the DPLL's autoidle state across the stop, per the CDP
* code. If DPLL3 was passed in, or the DPLL does not support
* low-power stop, return -EINVAL; otherwise, return 0.
*/
static int _omap3_noncore_dpll_stop(struct clk_hw_omap *clk)
{
u8 ai;
if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
return -EINVAL;
pr_debug("clock: stopping DPLL %s\n", __clk_get_name(clk->hw.clk));
ai = omap3_dpll_autoidle_read(clk);
_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);
if (ai)
omap3_dpll_allow_idle(clk);
return 0;
}
/**
* _lookup_dco - Lookup DCO used by j-type DPLL
* @clk: pointer to a DPLL struct clk
* @dco: digital control oscillator selector
* @m: DPLL multiplier to set
* @n: DPLL divider to set
*
* See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
*
* XXX This code is not needed for 3430/AM35xx; can it be optimized
* out in non-multi-OMAP builds for those chips?
*/
static void _lookup_dco(struct clk_hw_omap *clk, u8 *dco, u16 m, u8 n)
{
unsigned long fint, clkinp; /* watch out for overflow */
clkinp = __clk_get_rate(__clk_get_parent(clk->hw.clk));
fint = (clkinp / n) * m;
if (fint < 1000000000)
*dco = 2;
else
*dco = 4;
}
/**
* _lookup_sddiv - Calculate sigma delta divider for j-type DPLL
* @clk: pointer to a DPLL struct clk
* @sd_div: target sigma-delta divider
* @m: DPLL multiplier to set
* @n: DPLL divider to set
*
* See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
*
* XXX This code is not needed for 3430/AM35xx; can it be optimized
* out in non-multi-OMAP builds for those chips?
*/
static void _lookup_sddiv(struct clk_hw_omap *clk, u8 *sd_div, u16 m, u8 n)
{
unsigned long clkinp, sd; /* watch out for overflow */
int mod1, mod2;
clkinp = __clk_get_rate(__clk_get_parent(clk->hw.clk));
/*
* target sigma-delta to near 250MHz
* sd = ceil[(m/(n+1)) * (clkinp_MHz / 250)]
*/
clkinp /= 100000; /* shift from MHz to 10*Hz for 38.4 and 19.2 */
mod1 = (clkinp * m) % (250 * n);
sd = (clkinp * m) / (250 * n);
mod2 = sd % 10;
sd /= 10;
if (mod1 || mod2)
sd++;
*sd_div = sd;
}
/*
* _omap3_noncore_dpll_program - set non-core DPLL M,N values directly
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
* @clk: struct clk * of DPLL to set
* @freqsel: FREQSEL value to set
*
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
* Program the DPLL with the last M, N values calculated, and wait for
* the DPLL to lock. Returns -EINVAL upon error, or 0 upon success.
*/
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
static int omap3_noncore_dpll_program(struct clk_hw_omap *clk, u16 freqsel)
{
struct dpll_data *dd = clk->dpll_data;
u8 dco, sd_div;
u32 v;
/* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
_omap3_noncore_dpll_bypass(clk);
/*
* Set jitter correction. Jitter correction applicable for OMAP343X
* only since freqsel field is no longer present on other devices.
*/
if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
v = omap2_clk_readl(clk, dd->control_reg);
v &= ~dd->freqsel_mask;
v |= freqsel << __ffs(dd->freqsel_mask);
omap2_clk_writel(v, clk, dd->control_reg);
}
/* Set DPLL multiplier, divider */
v = omap2_clk_readl(clk, dd->mult_div1_reg);
/* Handle Duty Cycle Correction */
if (dd->dcc_mask) {
if (dd->last_rounded_rate >= dd->dcc_rate)
v |= dd->dcc_mask; /* Enable DCC */
else
v &= ~dd->dcc_mask; /* Disable DCC */
}
v &= ~(dd->mult_mask | dd->div1_mask);
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
v |= dd->last_rounded_m << __ffs(dd->mult_mask);
v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
/* Configure dco and sd_div for dplls that have these fields */
if (dd->dco_mask) {
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
_lookup_dco(clk, &dco, dd->last_rounded_m, dd->last_rounded_n);
v &= ~(dd->dco_mask);
v |= dco << __ffs(dd->dco_mask);
}
if (dd->sddiv_mask) {
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
_lookup_sddiv(clk, &sd_div, dd->last_rounded_m,
dd->last_rounded_n);
v &= ~(dd->sddiv_mask);
v |= sd_div << __ffs(dd->sddiv_mask);
}
omap2_clk_writel(v, clk, dd->mult_div1_reg);
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
/* Set 4X multiplier and low-power mode */
if (dd->m4xen_mask || dd->lpmode_mask) {
v = omap2_clk_readl(clk, dd->control_reg);
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
if (dd->m4xen_mask) {
if (dd->last_rounded_m4xen)
v |= dd->m4xen_mask;
else
v &= ~dd->m4xen_mask;
}
if (dd->lpmode_mask) {
if (dd->last_rounded_lpmode)
v |= dd->lpmode_mask;
else
v &= ~dd->lpmode_mask;
}
omap2_clk_writel(v, clk, dd->control_reg);
ARM: OMAP4: Enhance support for DPLLs with 4X multiplier On OMAP4 devices, the ABE DPLL has an internal 4X multiplier that can be enabled or disabled in addition to the standard configurable multiplier (M) for OMAP DPLLs. When configuring the ABE DPLL the 4X multiplier is accounted for by checking to see whether it is enabled or not. However, when calculating a new rate we only check to see if the rate can be achieved with the current setting for the 4X multiplier. Enhance the round_rate() function for such DPLLs to see if the rate can be achieved with the 4X multiplier if it cannot be achieved without the 4X multiplier. This change is necessary, because when using the 32kHz clock as the source clock for the ABE DPLL, the default DPLL frequency for the ABE DPLL cannot be achieved without enabling the 4X multiplier. When using the 32kHz clock as the source clock for the ABE DPLL and attempting to lock the DPLL to 98.304MHz (default frequency), it was found that the DPLL would fail to lock if the low-power mode for the DPLL was not enabled. From reviewing boot-loader settings that configure the ABE DPLL it was found that the low-power mode is enabled when using the 32kHz clock source, however, the documentation for OMAP does not state that this is a requirement. Therefore, introduce a new function for OMAP4 devices to see if low-power mode can be enabled when calculating a new rate to ensure the DPLL will lock. New variables for the last calculated 4X multiplier and low-power setting have been added to the dpll data structure as well as variables defining the bit mask for enabling these features via the DPLL's control_reg. It is possible that we could eliminate these bit masks from the dpll data structure as these bit masks are not unique to OMAP4, if it is preferred. The function omap3_noncore_program_dpll() has been updated to avoid passing the calculated values for the multiplier (M) and divider (N) as these are stored in the clk structure. Signed-off-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-12-15 01:35:46 -07:00
}
/* We let the clock framework set the other output dividers later */
/* REVISIT: Set ramp-up delay? */
_omap3_noncore_dpll_lock(clk);
return 0;
}
/* Public functions */
/**
* omap3_dpll_recalc - recalculate DPLL rate
* @clk: DPLL struct clk
*
* Recalculate and propagate the DPLL rate.
*/
unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
return omap2_get_dpll_rate(clk);
}
/* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */
/**
* omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
* @clk: pointer to a DPLL struct clk
*
* Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
* The choice of modes depends on the DPLL's programmed rate: if it is
* the same as the DPLL's parent clock, it will enter bypass;
* otherwise, it will enter lock. This code will wait for the DPLL to
* indicate readiness before returning, unless the DPLL takes too long
* to enter the target state. Intended to be used as the struct clk's
* enable function. If DPLL3 was passed in, or the DPLL does not
* support low-power stop, or if the DPLL took too long to enter
* bypass or lock, return -EINVAL; otherwise, return 0.
*/
int omap3_noncore_dpll_enable(struct clk_hw *hw)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
int r;
struct dpll_data *dd;
struct clk_hw *parent;
dd = clk->dpll_data;
if (!dd)
return -EINVAL;
if (clk->clkdm) {
r = clkdm_clk_enable(clk->clkdm, hw->clk);
if (r) {
WARN(1,
"%s: could not enable %s's clockdomain %s: %d\n",
__func__, __clk_get_name(hw->clk),
clk->clkdm->name, r);
return r;
}
}
parent = __clk_get_hw(__clk_get_parent(hw->clk));
if (__clk_get_rate(hw->clk) == __clk_get_rate(dd->clk_bypass)) {
WARN_ON(parent != __clk_get_hw(dd->clk_bypass));
r = _omap3_noncore_dpll_bypass(clk);
} else {
WARN_ON(parent != __clk_get_hw(dd->clk_ref));
r = _omap3_noncore_dpll_lock(clk);
}
return r;
}
/**
* omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop
* @clk: pointer to a DPLL struct clk
*
* Instructs a non-CORE DPLL to enter low-power stop. This function is
* intended for use in struct clkops. No return value.
*/
void omap3_noncore_dpll_disable(struct clk_hw *hw)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
_omap3_noncore_dpll_stop(clk);
if (clk->clkdm)
clkdm_clk_disable(clk->clkdm, hw->clk);
}
/* Non-CORE DPLL rate set code */
/**
* omap3_noncore_dpll_determine_rate - determine rate for a DPLL
* @hw: pointer to the clock to determine rate for
* @rate: target rate for the DPLL
* @best_parent_rate: pointer for returning best parent rate
* @best_parent_clk: pointer for returning best parent clock
*
* Determines which DPLL mode to use for reaching a desired target rate.
* Checks whether the DPLL shall be in bypass or locked mode, and if
* locked, calculates the M,N values for the DPLL via round-rate.
* Returns a positive clock rate with success, negative error value
* in failure.
*/
long omap3_noncore_dpll_determine_rate(struct clk_hw *hw, unsigned long rate,
unsigned long min_rate,
unsigned long max_rate,
unsigned long *best_parent_rate,
struct clk_hw **best_parent_clk)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
struct dpll_data *dd;
if (!hw || !rate)
return -EINVAL;
dd = clk->dpll_data;
if (!dd)
return -EINVAL;
if (__clk_get_rate(dd->clk_bypass) == rate &&
(dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
*best_parent_clk = __clk_get_hw(dd->clk_bypass);
} else {
rate = omap2_dpll_round_rate(hw, rate, best_parent_rate);
*best_parent_clk = __clk_get_hw(dd->clk_ref);
}
*best_parent_rate = rate;
return rate;
}
/**
* omap3_noncore_dpll_set_parent - set parent for a DPLL clock
* @hw: pointer to the clock to set parent for
* @index: parent index to select
*
* Sets parent for a DPLL clock. This sets the DPLL into bypass or
* locked mode. Returns 0 with success, negative error value otherwise.
*/
int omap3_noncore_dpll_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
int ret;
if (!hw)
return -EINVAL;
if (index)
ret = _omap3_noncore_dpll_bypass(clk);
else
ret = _omap3_noncore_dpll_lock(clk);
return ret;
}
/**
* omap3_noncore_dpll_set_rate - set rate for a DPLL clock
* @hw: pointer to the clock to set parent for
* @rate: target rate for the clock
* @parent_rate: rate of the parent clock
*
* Sets rate for a DPLL clock. First checks if the clock parent is
* reference clock (in bypass mode, the rate of the clock can't be
* changed) and proceeds with the rate change operation. Returns 0
* with success, negative error value otherwise.
*/
int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
struct dpll_data *dd;
u16 freqsel = 0;
int ret;
if (!hw || !rate)
return -EINVAL;
dd = clk->dpll_data;
if (!dd)
return -EINVAL;
if (__clk_get_hw(__clk_get_parent(hw->clk)) !=
__clk_get_hw(dd->clk_ref))
return -EINVAL;
if (dd->last_rounded_rate == 0)
return -EINVAL;
/* Freqsel is available only on OMAP343X devices */
if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
WARN_ON(!freqsel);
}
pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__,
__clk_get_name(hw->clk), rate);
ret = omap3_noncore_dpll_program(clk, freqsel);
return ret;
}
/**
* omap3_noncore_dpll_set_rate_and_parent - set rate and parent for a DPLL clock
* @hw: pointer to the clock to set rate and parent for
* @rate: target rate for the DPLL
* @parent_rate: clock rate of the DPLL parent
* @index: new parent index for the DPLL, 0 - reference, 1 - bypass
*
* Sets rate and parent for a DPLL clock. If new parent is the bypass
* clock, only selects the parent. Otherwise proceeds with a rate
* change, as this will effectively also change the parent as the
* DPLL is put into locked mode. Returns 0 with success, negative error
* value otherwise.
*/
int omap3_noncore_dpll_set_rate_and_parent(struct clk_hw *hw,
unsigned long rate,
unsigned long parent_rate,
u8 index)
{
int ret;
if (!hw || !rate)
return -EINVAL;
/*
* clk-ref at index[0], in which case we only need to set rate,
* the parent will be changed automatically with the lock sequence.
* With clk-bypass case we only need to change parent.
*/
if (index)
ret = omap3_noncore_dpll_set_parent(hw, index);
else
ret = omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
return ret;
}
/* DPLL autoidle read/set code */
/**
* omap3_dpll_autoidle_read - read a DPLL's autoidle bits
* @clk: struct clk * of the DPLL to read
*
* Return the DPLL's autoidle bits, shifted down to bit 0. Returns
* -EINVAL if passed a null pointer or if the struct clk does not
* appear to refer to a DPLL.
*/
u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk)
{
const struct dpll_data *dd;
u32 v;
if (!clk || !clk->dpll_data)
return -EINVAL;
dd = clk->dpll_data;
if (!dd->autoidle_reg)
return -EINVAL;
v = omap2_clk_readl(clk, dd->autoidle_reg);
v &= dd->autoidle_mask;
v >>= __ffs(dd->autoidle_mask);
return v;
}
/**
* omap3_dpll_allow_idle - enable DPLL autoidle bits
* @clk: struct clk * of the DPLL to operate on
*
* Enable DPLL automatic idle control. This automatic idle mode
* switching takes effect only when the DPLL is locked, at least on
* OMAP3430. The DPLL will enter low-power stop when its downstream
* clocks are gated. No return value.
*/
void omap3_dpll_allow_idle(struct clk_hw_omap *clk)
{
const struct dpll_data *dd;
u32 v;
if (!clk || !clk->dpll_data)
return;
dd = clk->dpll_data;
if (!dd->autoidle_reg)
return;
/*
* REVISIT: CORE DPLL can optionally enter low-power bypass
* by writing 0x5 instead of 0x1. Add some mechanism to
* optionally enter this mode.
*/
v = omap2_clk_readl(clk, dd->autoidle_reg);
v &= ~dd->autoidle_mask;
v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask);
omap2_clk_writel(v, clk, dd->autoidle_reg);
}
/**
* omap3_dpll_deny_idle - prevent DPLL from automatically idling
* @clk: struct clk * of the DPLL to operate on
*
* Disable DPLL automatic idle control. No return value.
*/
void omap3_dpll_deny_idle(struct clk_hw_omap *clk)
{
const struct dpll_data *dd;
u32 v;
if (!clk || !clk->dpll_data)
return;
dd = clk->dpll_data;
if (!dd->autoidle_reg)
return;
v = omap2_clk_readl(clk, dd->autoidle_reg);
v &= ~dd->autoidle_mask;
v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask);
omap2_clk_writel(v, clk, dd->autoidle_reg);
}
/* Clock control for DPLL outputs */
/* Find the parent DPLL for the given clkoutx2 clock */
static struct clk_hw_omap *omap3_find_clkoutx2_dpll(struct clk_hw *hw)
{
struct clk_hw_omap *pclk = NULL;
struct clk *parent;
/* Walk up the parents of clk, looking for a DPLL */
do {
do {
parent = __clk_get_parent(hw->clk);
hw = __clk_get_hw(parent);
} while (hw && (__clk_get_flags(hw->clk) & CLK_IS_BASIC));
if (!hw)
break;
pclk = to_clk_hw_omap(hw);
} while (pclk && !pclk->dpll_data);
/* clk does not have a DPLL as a parent? error in the clock data */
if (!pclk) {
WARN_ON(1);
return NULL;
}
return pclk;
}
/**
* omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
* @clk: DPLL output struct clk
*
* Using parent clock DPLL data, look up DPLL state. If locked, set our
* rate to the dpll_clk * 2; otherwise, just use dpll_clk.
*/
unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
unsigned long parent_rate)
{
const struct dpll_data *dd;
unsigned long rate;
u32 v;
struct clk_hw_omap *pclk = NULL;
if (!parent_rate)
return 0;
pclk = omap3_find_clkoutx2_dpll(hw);
if (!pclk)
ARM: OMAP: clean up some smatch warnings, fix some printk(KERN_ERR ... Resolve the following warnings from smatch: arch/arm/mach-omap2/gpmc.c:282 gpmc_cs_set_timings() info: why not propagate 'div' from gpmc_cs_calc_divider() instead of -1? arch/arm/mach-omap2/serial.c:328 omap_serial_init_port() error: 'pdev' dereferencing possible ERR_PTR() arch/arm/mach-omap2/timer.c:213 omap2_gp_clockevent_init() Error invalid range 4096 to -1 arch/arm/mach-omap2/gpio.c:63 omap2_gpio_dev_init() warn: possible memory leak of 'pdata' arch/arm/mach-omap2/omap_hwmod.c:1478 _assert_hardreset() warn: assigning -22 to unsigned variable 'ret' arch/arm/mach-omap2/omap_hwmod.c:1487 _assert_hardreset() warn: 4294963201 is more than 255 (max '(ret)' can be) so this is always the same. arch/arm/mach-omap2/omap_hwmod.c:1545 _read_hardreset() warn: assigning -22 to unsigned variable 'ret' arch/arm/mach-omap2/omap_hwmod.c:1554 _read_hardreset() warn: 4294963201 is more than 255 (max '(ret)' can be) so this is always the same. arch/arm/mach-omap2/dpll3xxx.c:629 omap3_clkoutx2_recalc() error: we previously assumed 'pclk' could be null (see line 627) arch/arm/mach-omap2/board-n8x0.c:422 n8x0_mmc_late_init() Error invalid range 14 to 13 arch/arm/mach-omap1/leds-h2p2-debug.c:71 h2p2_dbg_leds_event() error: potentially derefencing uninitialized 'fpga'. arch/arm/plat-omap/mux.c:79 omap_cfg_reg() Error invalid range 4096 to -1 Thanks to Tony Lindgren <tony@atomide.com> for pointing out that BUG() can be disabled. The changes in the first version that removed the subsequent return() after BUG() states have been dropped. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Tony Lindgren <tony@atomide.com>
2012-08-03 09:21:10 -06:00
return 0;
dd = pclk->dpll_data;
WARN_ON(!dd->enable_mask);
v = omap2_clk_readl(pclk, dd->control_reg) & dd->enable_mask;
v >>= __ffs(dd->enable_mask);
if ((v != OMAP3XXX_EN_DPLL_LOCKED) || (dd->flags & DPLL_J_TYPE))
rate = parent_rate;
else
rate = parent_rate * 2;
return rate;
}
int omap3_clkoutx2_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
return 0;
}
long omap3_clkoutx2_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
const struct dpll_data *dd;
u32 v;
struct clk_hw_omap *pclk = NULL;
if (!*prate)
return 0;
pclk = omap3_find_clkoutx2_dpll(hw);
if (!pclk)
return 0;
dd = pclk->dpll_data;
/* TYPE J does not have a clkoutx2 */
if (dd->flags & DPLL_J_TYPE) {
*prate = __clk_round_rate(__clk_get_parent(pclk->hw.clk), rate);
return *prate;
}
WARN_ON(!dd->enable_mask);
v = omap2_clk_readl(pclk, dd->control_reg) & dd->enable_mask;
v >>= __ffs(dd->enable_mask);
/* If in bypass, the rate is fixed to the bypass rate*/
if (v != OMAP3XXX_EN_DPLL_LOCKED)
return *prate;
if (__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT) {
unsigned long best_parent;
best_parent = (rate / 2);
*prate = __clk_round_rate(__clk_get_parent(hw->clk),
best_parent);
}
return *prate * 2;
}
/* OMAP3/4 non-CORE DPLL clkops */
const struct clk_hw_omap_ops clkhwops_omap3_dpll = {
.allow_idle = omap3_dpll_allow_idle,
.deny_idle = omap3_dpll_deny_idle,
};