u-boot/drivers/clk/sifive/sifive-prci.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018-2021 SiFive, Inc.
* Wesley Terpstra
* Paul Walmsley
* Zong Li
* Pragnesh Patel
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* The PRCI implements clock and reset control for the SiFive chip.
* This driver assumes that it has sole control over all PRCI resources.
*
* This driver is based on the PRCI driver written by Wesley Terpstra:
* https://github.com/riscv/riscv-linux/commit/999529edf517ed75b56659d456d221b2ee56bb60
*/
#include <common.h>
#include <clk-uclass.h>
#include <clk.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <reset.h>
#include <asm/io.h>
#include <asm/arch/reset.h>
#include <linux/delay.h>
#include <linux/math64.h>
#include <dt-bindings/clock/sifive-fu740-prci.h>
#include "fu540-prci.h"
#include "fu740-prci.h"
/*
* Private functions
*/
/**
* __prci_readl() - read from a PRCI register
* @pd: PRCI context
* @offs: register offset to read from (in bytes, from PRCI base address)
*
* Read the register located at offset @offs from the base virtual
* address of the PRCI register target described by @pd, and return
* the value to the caller.
*
* Context: Any context.
*
* Return: the contents of the register described by @pd and @offs.
*/
static u32 __prci_readl(struct __prci_data *pd, u32 offs)
{
return readl(pd->va + offs);
}
static void __prci_writel(u32 v, u32 offs, struct __prci_data *pd)
{
writel(v, pd->va + offs);
}
/* WRPLL-related private functions */
/**
* __prci_wrpll_unpack() - unpack WRPLL configuration registers into parameters
* @c: ptr to a struct wrpll_cfg record to write config into
* @r: value read from the PRCI PLL configuration register
*
* Given a value @r read from an FU540 PRCI PLL configuration register,
* split it into fields and populate it into the WRPLL configuration record
* pointed to by @c.
*
* The COREPLLCFG0 macros are used below, but the other *PLLCFG0 macros
* have the same register layout.
*
* Context: Any context.
*/
static void __prci_wrpll_unpack(struct wrpll_cfg *c, u32 r)
{
u32 v;
v = r & PRCI_COREPLLCFG0_DIVR_MASK;
v >>= PRCI_COREPLLCFG0_DIVR_SHIFT;
c->divr = v;
v = r & PRCI_COREPLLCFG0_DIVF_MASK;
v >>= PRCI_COREPLLCFG0_DIVF_SHIFT;
c->divf = v;
v = r & PRCI_COREPLLCFG0_DIVQ_MASK;
v >>= PRCI_COREPLLCFG0_DIVQ_SHIFT;
c->divq = v;
v = r & PRCI_COREPLLCFG0_RANGE_MASK;
v >>= PRCI_COREPLLCFG0_RANGE_SHIFT;
c->range = v;
c->flags &= (WRPLL_FLAGS_INT_FEEDBACK_MASK |
WRPLL_FLAGS_EXT_FEEDBACK_MASK);
/* external feedback mode not supported */
c->flags |= WRPLL_FLAGS_INT_FEEDBACK_MASK;
}
/**
* __prci_wrpll_pack() - pack PLL configuration parameters into a register value
* @c: pointer to a struct wrpll_cfg record containing the PLL's cfg
*
* Using a set of WRPLL configuration values pointed to by @c,
* assemble a PRCI PLL configuration register value, and return it to
* the caller.
*
* Context: Any context. Caller must ensure that the contents of the
* record pointed to by @c do not change during the execution
* of this function.
*
* Returns: a value suitable for writing into a PRCI PLL configuration
* register
*/
static u32 __prci_wrpll_pack(const struct wrpll_cfg *c)
{
u32 r = 0;
r |= c->divr << PRCI_COREPLLCFG0_DIVR_SHIFT;
r |= c->divf << PRCI_COREPLLCFG0_DIVF_SHIFT;
r |= c->divq << PRCI_COREPLLCFG0_DIVQ_SHIFT;
r |= c->range << PRCI_COREPLLCFG0_RANGE_SHIFT;
/* external feedback mode not supported */
r |= PRCI_COREPLLCFG0_FSE_MASK;
return r;
}
/**
* __prci_wrpll_read_cfg0() - read the WRPLL configuration from the PRCI
* @pd: PRCI context
* @pwd: PRCI WRPLL metadata
*
* Read the current configuration of the PLL identified by @pwd from
* the PRCI identified by @pd, and store it into the local configuration
* cache in @pwd.
*
* Context: Any context. Caller must prevent the records pointed to by
* @pd and @pwd from changing during execution.
*/
static void __prci_wrpll_read_cfg0(struct __prci_data *pd,
struct __prci_wrpll_data *pwd)
{
__prci_wrpll_unpack(&pwd->c, __prci_readl(pd, pwd->cfg0_offs));
}
/**
* __prci_wrpll_write_cfg0() - write WRPLL configuration into the PRCI
* @pd: PRCI context
* @pwd: PRCI WRPLL metadata
* @c: WRPLL configuration record to write
*
* Write the WRPLL configuration described by @c into the WRPLL
* configuration register identified by @pwd in the PRCI instance
* described by @c. Make a cached copy of the WRPLL's current
* configuration so it can be used by other code.
*
* Context: Any context. Caller must prevent the records pointed to by
* @pd and @pwd from changing during execution.
*/
static void __prci_wrpll_write_cfg0(struct __prci_data *pd,
struct __prci_wrpll_data *pwd,
struct wrpll_cfg *c)
{
__prci_writel(__prci_wrpll_pack(c), pwd->cfg0_offs, pd);
memcpy(&pwd->c, c, sizeof(*c));
}
/**
* __prci_wrpll_write_cfg1() - write Clock enable/disable configuration
* into the PRCI
* @pd: PRCI context
* @pwd: PRCI WRPLL metadata
* @enable: Clock enable or disable value
*/
static void __prci_wrpll_write_cfg1(struct __prci_data *pd,
struct __prci_wrpll_data *pwd,
u32 enable)
{
__prci_writel(enable, pwd->cfg1_offs, pd);
}
unsigned long sifive_prci_wrpll_recalc_rate(struct __prci_clock *pc,
unsigned long parent_rate)
{
struct __prci_wrpll_data *pwd = pc->pwd;
return wrpll_calc_output_rate(&pwd->c, parent_rate);
}
unsigned long sifive_prci_wrpll_round_rate(struct __prci_clock *pc,
unsigned long rate,
unsigned long *parent_rate)
{
struct __prci_wrpll_data *pwd = pc->pwd;
struct wrpll_cfg c;
memcpy(&c, &pwd->c, sizeof(c));
wrpll_configure_for_rate(&c, rate, *parent_rate);
return wrpll_calc_output_rate(&c, *parent_rate);
}
int sifive_prci_wrpll_set_rate(struct __prci_clock *pc,
unsigned long rate,
unsigned long parent_rate)
{
struct __prci_wrpll_data *pwd = pc->pwd;
struct __prci_data *pd = pc->pd;
int r;
r = wrpll_configure_for_rate(&pwd->c, rate, parent_rate);
if (r)
return r;
if (pwd->enable_bypass)
pwd->enable_bypass(pd);
__prci_wrpll_write_cfg0(pd, pwd, &pwd->c);
udelay(wrpll_calc_max_lock_us(&pwd->c));
return 0;
}
int sifive_prci_clock_enable(struct __prci_clock *pc, bool enable)
{
struct __prci_wrpll_data *pwd = pc->pwd;
struct __prci_data *pd = pc->pd;
if (enable) {
__prci_wrpll_write_cfg1(pd, pwd, PRCI_COREPLLCFG1_CKE_MASK);
if (pwd->disable_bypass)
pwd->disable_bypass(pd);
if (pwd->release_reset)
pwd->release_reset(pd);
} else {
u32 r;
if (pwd->enable_bypass)
pwd->enable_bypass(pd);
r = __prci_readl(pd, pwd->cfg1_offs);
r &= ~PRCI_COREPLLCFG1_CKE_MASK;
__prci_wrpll_write_cfg1(pd, pwd, r);
}
return 0;
}
/* TLCLKSEL clock integration */
unsigned long sifive_prci_tlclksel_recalc_rate(struct __prci_clock *pc,
unsigned long parent_rate)
{
struct __prci_data *pd = pc->pd;
u32 v;
u8 div;
v = __prci_readl(pd, PRCI_CLKMUXSTATUSREG_OFFSET);
v &= PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK;
div = v ? 1 : 2;
return div_u64(parent_rate, div);
}
/* HFPCLK clock integration */
unsigned long sifive_prci_hfpclkplldiv_recalc_rate(struct __prci_clock *pc,
unsigned long parent_rate)
{
struct __prci_data *pd = pc->pd;
u32 div = __prci_readl(pd, PRCI_HFPCLKPLLDIV_OFFSET);
return div_u64(parent_rate, div + 2);
}
/**
* sifive_prci_coreclksel_use_final_corepll() - switch the CORECLK mux to output
* FINAL_COREPLL
* @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg
*
* Switch the CORECLK mux to the final COREPLL output clock; return once
* complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_CORECLKSEL_OFFSET register.
*/
void sifive_prci_coreclksel_use_final_corepll(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET);
r &= ~PRCI_CORECLKSEL_CORECLKSEL_MASK;
__prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */
}
/**
* sifive_prci_corepllsel_use_dvfscorepll() - switch the COREPLL mux to
* output DVFS_COREPLL
* @pd: struct __prci_data * for the PRCI containing the COREPLL mux reg
*
* Switch the COREPLL mux to the DVFSCOREPLL output clock; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_COREPLLSEL_OFFSET register.
*/
void sifive_prci_corepllsel_use_dvfscorepll(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET);
r |= PRCI_COREPLLSEL_COREPLLSEL_MASK;
__prci_writel(r, PRCI_COREPLLSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); /* barrier */
}
/**
* sifive_prci_corepllsel_use_corepll() - switch the COREPLL mux to
* output COREPLL
* @pd: struct __prci_data * for the PRCI containing the COREPLL mux reg
*
* Switch the COREPLL mux to the COREPLL output clock; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_COREPLLSEL_OFFSET register.
*/
void sifive_prci_corepllsel_use_corepll(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET);
r &= ~PRCI_COREPLLSEL_COREPLLSEL_MASK;
__prci_writel(r, PRCI_COREPLLSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_COREPLLSEL_OFFSET); /* barrier */
}
/**
* sifive_prci_hfpclkpllsel_use_hfclk() - switch the HFPCLKPLL mux to
* output HFCLK
* @pd: struct __prci_data * for the PRCI containing the HFPCLKPLL mux reg
*
* Switch the HFPCLKPLL mux to the HFCLK input source; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_HFPCLKPLLSEL_OFFSET register.
*/
void sifive_prci_hfpclkpllsel_use_hfclk(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET);
r |= PRCI_HFPCLKPLLSEL_HFPCLKPLLSEL_MASK;
__prci_writel(r, PRCI_HFPCLKPLLSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); /* barrier */
}
/**
* sifive_prci_hfpclkpllsel_use_hfpclkpll() - switch the HFPCLKPLL mux to
* output HFPCLKPLL
* @pd: struct __prci_data * for the PRCI containing the HFPCLKPLL mux reg
*
* Switch the HFPCLKPLL mux to the HFPCLKPLL output clock; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_HFPCLKPLLSEL_OFFSET register.
*/
void sifive_prci_hfpclkpllsel_use_hfpclkpll(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET);
r &= ~PRCI_HFPCLKPLLSEL_HFPCLKPLLSEL_MASK;
__prci_writel(r, PRCI_HFPCLKPLLSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_HFPCLKPLLSEL_OFFSET); /* barrier */
}
static int __prci_consumer_reset(const char *rst_name, bool trigger)
{
struct udevice *dev;
struct reset_ctl rst_sig;
int ret;
ret = uclass_get_device_by_driver(UCLASS_RESET,
DM_DRIVER_GET(sifive_reset),
&dev);
if (ret) {
dev_err(dev, "Reset driver not found: %d\n", ret);
return ret;
}
ret = reset_get_by_name(dev, rst_name, &rst_sig);
if (ret) {
dev_err(dev, "failed to get %s reset\n", rst_name);
return ret;
}
if (reset_valid(&rst_sig)) {
if (trigger)
ret = reset_deassert(&rst_sig);
else
ret = reset_assert(&rst_sig);
if (ret) {
dev_err(dev, "failed to trigger reset id = %ld\n",
rst_sig.id);
return ret;
}
}
return ret;
}
/**
* sifive_prci_ddr_release_reset() - Release DDR reset
* @pd: struct __prci_data * for the PRCI containing the DDRCLK mux reg
*
*/
void sifive_prci_ddr_release_reset(struct __prci_data *pd)
{
/* Release DDR ctrl reset */
__prci_consumer_reset("ddr_ctrl", true);
/* HACK to get the '1 full controller clock cycle'. */
asm volatile ("fence");
/* Release DDR AXI reset */
__prci_consumer_reset("ddr_axi", true);
/* Release DDR AHB reset */
__prci_consumer_reset("ddr_ahb", true);
/* Release DDR PHY reset */
__prci_consumer_reset("ddr_phy", true);
/* HACK to get the '1 full controller clock cycle'. */
asm volatile ("fence");
/*
* These take like 16 cycles to actually propagate. We can't go sending
* stuff before they come out of reset. So wait.
*/
for (int i = 0; i < 256; i++)
asm volatile ("nop");
}
/**
* sifive_prci_ethernet_release_reset() - Release ethernet reset
* @pd: struct __prci_data * for the PRCI containing the Ethernet CLK mux reg
*
*/
void sifive_prci_ethernet_release_reset(struct __prci_data *pd)
{
/* Release GEMGXL reset */
__prci_consumer_reset("gemgxl_reset", true);
/* Procmon => core clock */
__prci_writel(PRCI_PROCMONCFG_CORE_CLOCK_MASK, PRCI_PROCMONCFG_OFFSET,
pd);
/* Release Chiplink reset */
__prci_consumer_reset("cltx_reset", true);
}
/**
* sifive_prci_cltx_release_reset() - Release cltx reset
* @pd: struct __prci_data * for the PRCI containing the Ethernet CLK mux reg
*
*/
void sifive_prci_cltx_release_reset(struct __prci_data *pd)
{
/* Release CLTX reset */
__prci_consumer_reset("cltx_reset", true);
}
/* Core clock mux control */
/**
* sifive_prci_coreclksel_use_hfclk() - switch the CORECLK mux to output HFCLK
* @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg
*
* Switch the CORECLK mux to the HFCLK input source; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_CORECLKSEL_OFFSET register.
*/
void sifive_prci_coreclksel_use_hfclk(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET);
r |= PRCI_CORECLKSEL_CORECLKSEL_MASK;
__prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */
}
/**
* sifive_prci_coreclksel_use_corepll() - switch the CORECLK mux to output COREPLL
* @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg
*
* Switch the CORECLK mux to the PLL output clock; return once complete.
*
* Context: Any context. Caller must prevent concurrent changes to the
* PRCI_CORECLKSEL_OFFSET register.
*/
void sifive_prci_coreclksel_use_corepll(struct __prci_data *pd)
{
u32 r;
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET);
r &= ~PRCI_CORECLKSEL_CORECLKSEL_MASK;
__prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd);
r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */
}
static ulong sifive_prci_parent_rate(struct __prci_clock *pc, struct prci_clk_desc *data)
{
ulong parent_rate;
ulong i;
struct __prci_clock *p;
if (strcmp(pc->parent_name, "corepll") == 0 ||
strcmp(pc->parent_name, "hfpclkpll") == 0) {
for (i = 0; i < data->num_clks; i++) {
if (strcmp(pc->parent_name, data->clks[i].name) == 0)
break;
}
if (i >= data->num_clks)
return -ENXIO;
p = &data->clks[i];
if (!p->pd || !p->ops->recalc_rate)
return -ENXIO;
return p->ops->recalc_rate(p, sifive_prci_parent_rate(p, data));
}
if (strcmp(pc->parent_name, "rtcclk") == 0)
parent_rate = clk_get_rate(&pc->pd->parent_rtcclk);
else
parent_rate = clk_get_rate(&pc->pd->parent_hfclk);
return parent_rate;
}
static ulong sifive_prci_get_rate(struct clk *clk)
{
struct __prci_clock *pc;
struct prci_clk_desc *data =
(struct prci_clk_desc *)dev_get_driver_data(clk->dev);
if (data->num_clks <= clk->id)
return -ENXIO;
pc = &data->clks[clk->id];
if (!pc->pd || !pc->ops->recalc_rate)
return -ENXIO;
return pc->ops->recalc_rate(pc, sifive_prci_parent_rate(pc, data));
}
static ulong sifive_prci_set_rate(struct clk *clk, ulong rate)
{
int err;
struct __prci_clock *pc;
struct prci_clk_desc *data =
(struct prci_clk_desc *)dev_get_driver_data(clk->dev);
if (data->num_clks <= clk->id)
return -ENXIO;
pc = &data->clks[clk->id];
if (!pc->pd || !pc->ops->set_rate)
return -ENXIO;
err = pc->ops->set_rate(pc, rate, sifive_prci_parent_rate(pc, data));
if (err)
return err;
return rate;
}
static int sifive_prci_enable(struct clk *clk)
{
struct __prci_clock *pc;
int ret = 0;
struct prci_clk_desc *data =
(struct prci_clk_desc *)dev_get_driver_data(clk->dev);
if (data->num_clks <= clk->id)
return -ENXIO;
pc = &data->clks[clk->id];
if (!pc->pd)
return -ENXIO;
if (pc->ops->enable_clk)
ret = pc->ops->enable_clk(pc, 1);
return ret;
}
static int sifive_prci_disable(struct clk *clk)
{
struct __prci_clock *pc;
int ret = 0;
struct prci_clk_desc *data =
(struct prci_clk_desc *)dev_get_driver_data(clk->dev);
if (data->num_clks <= clk->id)
return -ENXIO;
pc = &data->clks[clk->id];
if (!pc->pd)
return -ENXIO;
if (pc->ops->enable_clk)
ret = pc->ops->enable_clk(pc, 0);
return ret;
}
static int sifive_prci_probe(struct udevice *dev)
{
int i, err;
struct __prci_clock *pc;
struct __prci_data *pd = dev_get_priv(dev);
struct prci_clk_desc *data =
(struct prci_clk_desc *)dev_get_driver_data(dev);
pd->va = dev_read_addr_ptr(dev);
if (!pd->va)
return -EINVAL;
err = clk_get_by_index(dev, 0, &pd->parent_hfclk);
if (err)
return err;
err = clk_get_by_index(dev, 1, &pd->parent_rtcclk);
if (err)
return err;
for (i = 0; i < data->num_clks; ++i) {
pc = &data->clks[i];
pc->pd = pd;
if (pc->pwd)
__prci_wrpll_read_cfg0(pd, pc->pwd);
}
if (IS_ENABLED(CONFIG_SPL_BUILD)) {
if (device_is_compatible(dev, "sifive,fu740-c000-prci")) {
u32 prci_pll_reg;
unsigned long parent_rate;
prci_pll_reg = readl(pd->va + PRCI_PRCIPLL_OFFSET);
if (prci_pll_reg & PRCI_PRCIPLL_HFPCLKPLL) {
/*
* Only initialize the HFPCLK PLL. In this
* case the design uses hfpclk to drive
* Chiplink
*/
pc = &data->clks[PRCI_CLK_HFPCLKPLL];
parent_rate = sifive_prci_parent_rate(pc, data);
sifive_prci_wrpll_set_rate(pc, 260000000,
parent_rate);
pc->ops->enable_clk(pc, 1);
} else if (prci_pll_reg & PRCI_PRCIPLL_CLTXPLL) {
/* CLTX pll init */
pc = &data->clks[PRCI_CLK_CLTXPLL];
parent_rate = sifive_prci_parent_rate(pc, data);
sifive_prci_wrpll_set_rate(pc, 260000000,
parent_rate);
pc->ops->enable_clk(pc, 1);
}
}
}
return 0;
}
static struct clk_ops sifive_prci_ops = {
.set_rate = sifive_prci_set_rate,
.get_rate = sifive_prci_get_rate,
.enable = sifive_prci_enable,
.disable = sifive_prci_disable,
};
static int sifive_clk_bind(struct udevice *dev)
{
return sifive_reset_bind(dev, PRCI_DEVICERESETCNT);
}
static const struct udevice_id sifive_prci_ids[] = {
{ .compatible = "sifive,fu540-c000-prci", .data = (ulong)&prci_clk_fu540 },
{ .compatible = "sifive,fu740-c000-prci", .data = (ulong)&prci_clk_fu740 },
{ }
};
U_BOOT_DRIVER(sifive_prci) = {
.name = "sifive-prci",
.id = UCLASS_CLK,
.of_match = sifive_prci_ids,
.probe = sifive_prci_probe,
.ops = &sifive_prci_ops,
.priv_auto = sizeof(struct __prci_data),
.bind = sifive_clk_bind,
};