blob: 063b6115148869aa014216343cfa06407a30b77b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* R-Car Gen3 Clock Pulse Generator
*
* Copyright (C) 2015-2018 Glider bvba
* Copyright (C) 2019 Renesas Electronics Corp.
*
* Based on clk-rcar-gen3.c
*
* Copyright (C) 2015 Renesas Electronics Corp.
*/
#include <linux/bug.h>
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/sys_soc.h>
#include "renesas-cpg-mssr.h"
#include "rcar-gen3-cpg.h"
#define CPG_PLL0CR 0x00d8
#define CPG_PLL2CR 0x002c
#define CPG_PLL4CR 0x01f4
#define CPG_RCKCR_CKSEL BIT(15) /* RCLK Clock Source Select */
static spinlock_t cpg_lock;
static void cpg_reg_modify(void __iomem *reg, u32 clear, u32 set)
{
unsigned long flags;
u32 val;
spin_lock_irqsave(&cpg_lock, flags);
val = readl(reg);
val &= ~clear;
val |= set;
writel(val, reg);
spin_unlock_irqrestore(&cpg_lock, flags);
};
struct cpg_simple_notifier {
struct notifier_block nb;
void __iomem *reg;
u32 saved;
};
static int cpg_simple_notifier_call(struct notifier_block *nb,
unsigned long action, void *data)
{
struct cpg_simple_notifier *csn =
container_of(nb, struct cpg_simple_notifier, nb);
switch (action) {
case PM_EVENT_SUSPEND:
csn->saved = readl(csn->reg);
return NOTIFY_OK;
case PM_EVENT_RESUME:
writel(csn->saved, csn->reg);
return NOTIFY_OK;
}
return NOTIFY_DONE;
}
static void cpg_simple_notifier_register(struct raw_notifier_head *notifiers,
struct cpg_simple_notifier *csn)
{
csn->nb.notifier_call = cpg_simple_notifier_call;
raw_notifier_chain_register(notifiers, &csn->nb);
}
/*
* Z Clock & Z2 Clock
*
* Traits of this clock:
* prepare - clk_prepare only ensures that parents are prepared
* enable - clk_enable only ensures that parents are enabled
* rate - rate is adjustable. clk->rate = (parent->rate * mult / 32 ) / 2
* parent - fixed parent. No clk_set_parent support
*/
#define CPG_FRQCRB 0x00000004
#define CPG_FRQCRB_KICK BIT(31)
#define CPG_FRQCRC 0x000000e0
struct cpg_z_clk {
struct clk_hw hw;
void __iomem *reg;
void __iomem *kick_reg;
unsigned long mask;
unsigned int fixed_div;
};
#define to_z_clk(_hw) container_of(_hw, struct cpg_z_clk, hw)
static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct cpg_z_clk *zclk = to_z_clk(hw);
unsigned int mult;
u32 val;
val = readl(zclk->reg) & zclk->mask;
mult = 32 - (val >> __ffs(zclk->mask));
return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
32 * zclk->fixed_div);
}
static int cpg_z_clk_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct cpg_z_clk *zclk = to_z_clk(hw);
unsigned int min_mult, max_mult, mult;
unsigned long prate;
prate = req->best_parent_rate / zclk->fixed_div;
min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL);
max_mult = min(div64_ul(req->max_rate * 32ULL, prate), 32ULL);
if (max_mult < min_mult)
return -EINVAL;
mult = div64_ul(req->rate * 32ULL, prate);
mult = clamp(mult, min_mult, max_mult);
req->rate = div_u64((u64)prate * mult, 32);
return 0;
}
static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct cpg_z_clk *zclk = to_z_clk(hw);
unsigned int mult;
unsigned int i;
mult = DIV64_U64_ROUND_CLOSEST(rate * 32ULL * zclk->fixed_div,
parent_rate);
mult = clamp(mult, 1U, 32U);
if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
return -EBUSY;
cpg_reg_modify(zclk->reg, zclk->mask,
((32 - mult) << __ffs(zclk->mask)) & zclk->mask);
/*
* Set KICK bit in FRQCRB to update hardware setting and wait for
* clock change completion.
*/
cpg_reg_modify(zclk->kick_reg, 0, CPG_FRQCRB_KICK);
/*
* Note: There is no HW information about the worst case latency.
*
* Using experimental measurements, it seems that no more than
* ~10 iterations are needed, independently of the CPU rate.
* Since this value might be dependent of external xtal rate, pll1
* rate or even the other emulation clocks rate, use 1000 as a
* "super" safe value.
*/
for (i = 1000; i; i--) {
if (!(readl(zclk->kick_reg) & CPG_FRQCRB_KICK))
return 0;
cpu_relax();
}
return -ETIMEDOUT;
}
static const struct clk_ops cpg_z_clk_ops = {
.recalc_rate = cpg_z_clk_recalc_rate,
.determine_rate = cpg_z_clk_determine_rate,
.set_rate = cpg_z_clk_set_rate,
};
static struct clk * __init cpg_z_clk_register(const char *name,
const char *parent_name,
void __iomem *reg,
unsigned int div,
unsigned int offset)
{
struct clk_init_data init;
struct cpg_z_clk *zclk;
struct clk *clk;
zclk = kzalloc(sizeof(*zclk), GFP_KERNEL);
if (!zclk)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &cpg_z_clk_ops;
init.flags = 0;
init.parent_names = &parent_name;
init.num_parents = 1;
zclk->reg = reg + CPG_FRQCRC;
zclk->kick_reg = reg + CPG_FRQCRB;
zclk->hw.init = &init;
zclk->mask = GENMASK(offset + 4, offset);
zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */
clk = clk_register(NULL, &zclk->hw);
if (IS_ERR(clk))
kfree(zclk);
return clk;
}
/*
* SDn Clock
*/
#define CPG_SD_STP_HCK BIT(9)
#define CPG_SD_STP_CK BIT(8)
#define CPG_SD_STP_MASK (CPG_SD_STP_HCK | CPG_SD_STP_CK)
#define CPG_SD_FC_MASK (0x7 << 2 | 0x3 << 0)
#define CPG_SD_DIV_TABLE_DATA(stp_hck, sd_srcfc, sd_fc, sd_div) \
{ \
.val = ((stp_hck) ? CPG_SD_STP_HCK : 0) | \
((sd_srcfc) << 2) | \
((sd_fc) << 0), \
.div = (sd_div), \
}
struct sd_div_table {
u32 val;
unsigned int div;
};
struct sd_clock {
struct clk_hw hw;
const struct sd_div_table *div_table;
struct cpg_simple_notifier csn;
unsigned int div_num;
unsigned int cur_div_idx;
};
/* SDn divider
* sd_srcfc sd_fc div
* stp_hck (div) (div) = sd_srcfc x sd_fc
*---------------------------------------------------------
* 0 0 (1) 1 (4) 4 : SDR104 / HS200 / HS400 (8 TAP)
* 0 1 (2) 1 (4) 8 : SDR50
* 1 2 (4) 1 (4) 16 : HS / SDR25
* 1 3 (8) 1 (4) 32 : NS / SDR12
* 1 4 (16) 1 (4) 64
* 0 0 (1) 0 (2) 2
* 0 1 (2) 0 (2) 4 : SDR104 / HS200 / HS400 (4 TAP)
* 1 2 (4) 0 (2) 8
* 1 3 (8) 0 (2) 16
* 1 4 (16) 0 (2) 32
*
* NOTE: There is a quirk option to ignore the first row of the dividers
* table when searching for suitable settings. This is because HS400 on
* early ES versions of H3 and M3-W requires a specific setting to work.
*/
static const struct sd_div_table cpg_sd_div_table[] = {
/* CPG_SD_DIV_TABLE_DATA(stp_hck, sd_srcfc, sd_fc, sd_div) */
CPG_SD_DIV_TABLE_DATA(0, 0, 1, 4),
CPG_SD_DIV_TABLE_DATA(0, 1, 1, 8),
CPG_SD_DIV_TABLE_DATA(1, 2, 1, 16),
CPG_SD_DIV_TABLE_DATA(1, 3, 1, 32),
CPG_SD_DIV_TABLE_DATA(1, 4, 1, 64),
CPG_SD_DIV_TABLE_DATA(0, 0, 0, 2),
CPG_SD_DIV_TABLE_DATA(0, 1, 0, 4),
CPG_SD_DIV_TABLE_DATA(1, 2, 0, 8),
CPG_SD_DIV_TABLE_DATA(1, 3, 0, 16),
CPG_SD_DIV_TABLE_DATA(1, 4, 0, 32),
};
#define to_sd_clock(_hw) container_of(_hw, struct sd_clock, hw)
static int cpg_sd_clock_enable(struct clk_hw *hw)
{
struct sd_clock *clock = to_sd_clock(hw);
cpg_reg_modify(clock->csn.reg, CPG_SD_STP_MASK,
clock->div_table[clock->cur_div_idx].val &
CPG_SD_STP_MASK);
return 0;
}
static void cpg_sd_clock_disable(struct clk_hw *hw)
{
struct sd_clock *clock = to_sd_clock(hw);
cpg_reg_modify(clock->csn.reg, 0, CPG_SD_STP_MASK);
}
static int cpg_sd_clock_is_enabled(struct clk_hw *hw)
{
struct sd_clock *clock = to_sd_clock(hw);
return !(readl(clock->csn.reg) & CPG_SD_STP_MASK);
}
static unsigned long cpg_sd_clock_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct sd_clock *clock = to_sd_clock(hw);
return DIV_ROUND_CLOSEST(parent_rate,
clock->div_table[clock->cur_div_idx].div);
}
static int cpg_sd_clock_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
unsigned long best_rate = ULONG_MAX, diff_min = ULONG_MAX;
struct sd_clock *clock = to_sd_clock(hw);
unsigned long calc_rate, diff;
unsigned int i;
for (i = 0; i < clock->div_num; i++) {
calc_rate = DIV_ROUND_CLOSEST(req->best_parent_rate,
clock->div_table[i].div);
if (calc_rate < req->min_rate || calc_rate > req->max_rate)
continue;
diff = calc_rate > req->rate ? calc_rate - req->rate
: req->rate - calc_rate;
if (diff < diff_min) {
best_rate = calc_rate;
diff_min = diff;
}
}
if (best_rate == ULONG_MAX)
return -EINVAL;
req->rate = best_rate;
return 0;
}
static int cpg_sd_clock_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct sd_clock *clock = to_sd_clock(hw);
unsigned int i;
for (i = 0; i < clock->div_num; i++)
if (rate == DIV_ROUND_CLOSEST(parent_rate,
clock->div_table[i].div))
break;
if (i >= clock->div_num)
return -EINVAL;
clock->cur_div_idx = i;
cpg_reg_modify(clock->csn.reg, CPG_SD_STP_MASK | CPG_SD_FC_MASK,
clock->div_table[i].val &
(CPG_SD_STP_MASK | CPG_SD_FC_MASK));
return 0;
}
static const struct clk_ops cpg_sd_clock_ops = {
.enable = cpg_sd_clock_enable,
.disable = cpg_sd_clock_disable,
.is_enabled = cpg_sd_clock_is_enabled,
.recalc_rate = cpg_sd_clock_recalc_rate,
.determine_rate = cpg_sd_clock_determine_rate,
.set_rate = cpg_sd_clock_set_rate,
};
static u32 cpg_quirks __initdata;
#define PLL_ERRATA BIT(0) /* Missing PLL0/2/4 post-divider */
#define RCKCR_CKSEL BIT(1) /* Manual RCLK parent selection */
#define SD_SKIP_FIRST BIT(2) /* Skip first clock in SD table */
static struct clk * __init cpg_sd_clk_register(const char *name,
void __iomem *base, unsigned int offset, const char *parent_name,
struct raw_notifier_head *notifiers)
{
struct clk_init_data init;
struct sd_clock *clock;
struct clk *clk;
u32 val;
clock = kzalloc(sizeof(*clock), GFP_KERNEL);
if (!clock)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &cpg_sd_clock_ops;
init.flags = CLK_SET_RATE_PARENT;
init.parent_names = &parent_name;
init.num_parents = 1;
clock->csn.reg = base + offset;
clock->hw.init = &init;
clock->div_table = cpg_sd_div_table;
clock->div_num = ARRAY_SIZE(cpg_sd_div_table);
if (cpg_quirks & SD_SKIP_FIRST) {
clock->div_table++;
clock->div_num--;
}
val = readl(clock->csn.reg) & ~CPG_SD_FC_MASK;
val |= CPG_SD_STP_MASK | (clock->div_table[0].val & CPG_SD_FC_MASK);
writel(val, clock->csn.reg);
clk = clk_register(NULL, &clock->hw);
if (IS_ERR(clk))
goto free_clock;
cpg_simple_notifier_register(notifiers, &clock->csn);
return clk;
free_clock:
kfree(clock);
return clk;
}
struct rpc_clock {
struct clk_divider div;
struct clk_gate gate;
/*
* One notifier covers both RPC and RPCD2 clocks as they are both
* controlled by the same RPCCKCR register...
*/
struct cpg_simple_notifier csn;
};
static const struct clk_div_table cpg_rpcsrc_div_table[] = {
{ 2, 5 }, { 3, 6 }, { 0, 0 },
};
static const struct clk_div_table cpg_rpc_div_table[] = {
{ 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 }, { 0, 0 },
};
static struct clk * __init cpg_rpc_clk_register(const char *name,
void __iomem *base, const char *parent_name,
struct raw_notifier_head *notifiers)
{
struct rpc_clock *rpc;
struct clk *clk;
rpc = kzalloc(sizeof(*rpc), GFP_KERNEL);
if (!rpc)
return ERR_PTR(-ENOMEM);
rpc->div.reg = base + CPG_RPCCKCR;
rpc->div.width = 3;
rpc->div.table = cpg_rpc_div_table;
rpc->div.lock = &cpg_lock;
rpc->gate.reg = base + CPG_RPCCKCR;
rpc->gate.bit_idx = 8;
rpc->gate.flags = CLK_GATE_SET_TO_DISABLE;
rpc->gate.lock = &cpg_lock;
rpc->csn.reg = base + CPG_RPCCKCR;
clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
&rpc->div.hw, &clk_divider_ops,
&rpc->gate.hw, &clk_gate_ops,
CLK_SET_RATE_PARENT);
if (IS_ERR(clk)) {
kfree(rpc);
return clk;
}
cpg_simple_notifier_register(notifiers, &rpc->csn);
return clk;
}
struct rpcd2_clock {
struct clk_fixed_factor fixed;
struct clk_gate gate;
};
static struct clk * __init cpg_rpcd2_clk_register(const char *name,
void __iomem *base,
const char *parent_name)
{
struct rpcd2_clock *rpcd2;
struct clk *clk;
rpcd2 = kzalloc(sizeof(*rpcd2), GFP_KERNEL);
if (!rpcd2)
return ERR_PTR(-ENOMEM);
rpcd2->fixed.mult = 1;
rpcd2->fixed.div = 2;
rpcd2->gate.reg = base + CPG_RPCCKCR;
rpcd2->gate.bit_idx = 9;
rpcd2->gate.flags = CLK_GATE_SET_TO_DISABLE;
rpcd2->gate.lock = &cpg_lock;
clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
&rpcd2->fixed.hw, &clk_fixed_factor_ops,
&rpcd2->gate.hw, &clk_gate_ops,
CLK_SET_RATE_PARENT);
if (IS_ERR(clk))
kfree(rpcd2);
return clk;
}
static const struct rcar_gen3_cpg_pll_config *cpg_pll_config __initdata;
static unsigned int cpg_clk_extalr __initdata;
static u32 cpg_mode __initdata;
static const struct soc_device_attribute cpg_quirks_match[] __initconst = {
{
.soc_id = "r8a7795", .revision = "ES1.0",
.data = (void *)(PLL_ERRATA | RCKCR_CKSEL | SD_SKIP_FIRST),
},
{
.soc_id = "r8a7795", .revision = "ES1.*",
.data = (void *)(RCKCR_CKSEL | SD_SKIP_FIRST),
},
{
.soc_id = "r8a7795", .revision = "ES2.0",
.data = (void *)SD_SKIP_FIRST,
},
{
.soc_id = "r8a7796", .revision = "ES1.0",
.data = (void *)(RCKCR_CKSEL | SD_SKIP_FIRST),
},
{
.soc_id = "r8a7796", .revision = "ES1.1",
.data = (void *)SD_SKIP_FIRST,
},
{ /* sentinel */ }
};
struct clk * __init rcar_gen3_cpg_clk_register(struct device *dev,
const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
struct clk **clks, void __iomem *base,
struct raw_notifier_head *notifiers)
{
const struct clk *parent;
unsigned int mult = 1;
unsigned int div = 1;
u32 value;
parent = clks[core->parent & 0xffff]; /* some types use high bits */
if (IS_ERR(parent))
return ERR_CAST(parent);
switch (core->type) {
case CLK_TYPE_GEN3_MAIN:
div = cpg_pll_config->extal_div;
break;
case CLK_TYPE_GEN3_PLL0:
/*
* PLL0 is a configurable multiplier clock. Register it as a
* fixed factor clock for now as there's no generic multiplier
* clock implementation and we currently have no need to change
* the multiplier value.
*/
value = readl(base + CPG_PLL0CR);
mult = (((value >> 24) & 0x7f) + 1) * 2;
if (cpg_quirks & PLL_ERRATA)
mult *= 2;
break;
case CLK_TYPE_GEN3_PLL1:
mult = cpg_pll_config->pll1_mult;
div = cpg_pll_config->pll1_div;
break;
case CLK_TYPE_GEN3_PLL2:
/*
* PLL2 is a configurable multiplier clock. Register it as a
* fixed factor clock for now as there's no generic multiplier
* clock implementation and we currently have no need to change
* the multiplier value.
*/
value = readl(base + CPG_PLL2CR);
mult = (((value >> 24) & 0x7f) + 1) * 2;
if (cpg_quirks & PLL_ERRATA)
mult *= 2;
break;
case CLK_TYPE_GEN3_PLL3:
mult = cpg_pll_config->pll3_mult;
div = cpg_pll_config->pll3_div;
break;
case CLK_TYPE_GEN3_PLL4:
/*
* PLL4 is a configurable multiplier clock. Register it as a
* fixed factor clock for now as there's no generic multiplier
* clock implementation and we currently have no need to change
* the multiplier value.
*/
value = readl(base + CPG_PLL4CR);
mult = (((value >> 24) & 0x7f) + 1) * 2;
if (cpg_quirks & PLL_ERRATA)
mult *= 2;
break;
case CLK_TYPE_GEN3_SD:
return cpg_sd_clk_register(core->name, base, core->offset,
__clk_get_name(parent), notifiers);
case CLK_TYPE_GEN3_R:
if (cpg_quirks & RCKCR_CKSEL) {
struct cpg_simple_notifier *csn;
csn = kzalloc(sizeof(*csn), GFP_KERNEL);
if (!csn)
return ERR_PTR(-ENOMEM);
csn->reg = base + CPG_RCKCR;
/*
* RINT is default.
* Only if EXTALR is populated, we switch to it.
*/
value = readl(csn->reg) & 0x3f;
if (clk_get_rate(clks[cpg_clk_extalr])) {
parent = clks[cpg_clk_extalr];
value |= CPG_RCKCR_CKSEL;
}
writel(value, csn->reg);
cpg_simple_notifier_register(notifiers, csn);
break;
}
/* Select parent clock of RCLK by MD28 */
if (cpg_mode & BIT(28))
parent = clks[cpg_clk_extalr];
break;
case CLK_TYPE_GEN3_MDSEL:
/*
* Clock selectable between two parents and two fixed dividers
* using a mode pin
*/
if (cpg_mode & BIT(core->offset)) {
div = core->div & 0xffff;
} else {
parent = clks[core->parent >> 16];
if (IS_ERR(parent))
return ERR_CAST(parent);
div = core->div >> 16;
}
mult = 1;
break;
case CLK_TYPE_GEN3_Z:
return cpg_z_clk_register(core->name, __clk_get_name(parent),
base, core->div, core->offset);
case CLK_TYPE_GEN3_OSC:
/*
* Clock combining OSC EXTAL predivider and a fixed divider
*/
div = cpg_pll_config->osc_prediv * core->div;
break;
case CLK_TYPE_GEN3_RCKSEL:
/*
* Clock selectable between two parents and two fixed dividers
* using RCKCR.CKSEL
*/
if (readl(base + CPG_RCKCR) & CPG_RCKCR_CKSEL) {
div = core->div & 0xffff;
} else {
parent = clks[core->parent >> 16];
if (IS_ERR(parent))
return ERR_CAST(parent);
div = core->div >> 16;
}
break;
case CLK_TYPE_GEN3_RPCSRC:
return clk_register_divider_table(NULL, core->name,
__clk_get_name(parent), 0,
base + CPG_RPCCKCR, 3, 2, 0,
cpg_rpcsrc_div_table,
&cpg_lock);
case CLK_TYPE_GEN3_E3_RPCSRC:
/*
* Register RPCSRC as fixed factor clock based on the
* MD[4:1] pins and CPG_RPCCKCR[4:3] register value for
* which has been set prior to booting the kernel.
*/
value = (readl(base + CPG_RPCCKCR) & GENMASK(4, 3)) >> 3;
switch (value) {
case 0:
div = 5;
break;
case 1:
div = 3;
break;
case 2:
parent = clks[core->parent >> 16];
if (IS_ERR(parent))
return ERR_CAST(parent);
div = core->div;
break;
case 3:
default:
div = 2;
break;
}
break;
case CLK_TYPE_GEN3_RPC:
return cpg_rpc_clk_register(core->name, base,
__clk_get_name(parent), notifiers);
case CLK_TYPE_GEN3_RPCD2:
return cpg_rpcd2_clk_register(core->name, base,
__clk_get_name(parent));
default:
return ERR_PTR(-EINVAL);
}
return clk_register_fixed_factor(NULL, core->name,
__clk_get_name(parent), 0, mult, div);
}
int __init rcar_gen3_cpg_init(const struct rcar_gen3_cpg_pll_config *config,
unsigned int clk_extalr, u32 mode)
{
const struct soc_device_attribute *attr;
cpg_pll_config = config;
cpg_clk_extalr = clk_extalr;
cpg_mode = mode;
attr = soc_device_match(cpg_quirks_match);
if (attr)
cpg_quirks = (uintptr_t)attr->data;
pr_debug("%s: mode = 0x%x quirks = 0x%x\n", __func__, mode, cpg_quirks);
spin_lock_init(&cpg_lock);
return 0;
}