u-boot/arch/arm/mach-snapdragon/clock-snapdragon.c

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/*
* Clock drivers for Qualcomm APQ8016, APQ8096
*
* (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
*
* Based on Little Kernel driver, simplified
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <errno.h>
#include <asm/io.h>
#include <linux/bitops.h>
#include "clock-snapdragon.h"
/* CBCR register fields */
#define CBCR_BRANCH_ENABLE_BIT BIT(0)
#define CBCR_BRANCH_OFF_BIT BIT(31)
extern ulong msm_set_rate(struct clk *clk, ulong rate);
/* Enable clock controlled by CBC soft macro */
void clk_enable_cbc(phys_addr_t cbcr)
{
setbits_le32(cbcr, CBCR_BRANCH_ENABLE_BIT);
while (readl(cbcr) & CBCR_BRANCH_OFF_BIT)
;
}
void clk_enable_gpll0(phys_addr_t base, const struct gpll0_ctrl *gpll0)
{
if (readl(base + gpll0->status) & gpll0->status_bit)
return; /* clock already enabled */
setbits_le32(base + gpll0->ena_vote, gpll0->vote_bit);
while ((readl(base + gpll0->status) & gpll0->status_bit) == 0)
;
}
#define APPS_CMD_RGCR_UPDATE BIT(0)
/* Update clock command via CMD_RGCR */
void clk_bcr_update(phys_addr_t apps_cmd_rgcr)
{
setbits_le32(apps_cmd_rgcr, APPS_CMD_RGCR_UPDATE);
/* Wait for frequency to be updated. */
while (readl(apps_cmd_rgcr) & APPS_CMD_RGCR_UPDATE)
;
}
#define CFG_MODE_DUAL_EDGE (0x2 << 12) /* Counter mode */
#define CFG_MASK 0x3FFF
#define CFG_DIVIDER_MASK 0x1F
/* root set rate for clocks with half integer and MND divider */
void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
int div, int m, int n, int source)
{
u32 cfg;
/* M value for MND divider. */
u32 m_val = m;
/* NOT(N-M) value for MND divider. */
u32 n_val = ~((n) - (m)) * !!(n);
/* NOT 2D value for MND divider. */
u32 d_val = ~(n);
/* Program MND values */
writel(m_val, base + regs->M);
writel(n_val, base + regs->N);
writel(d_val, base + regs->D);
/* setup src select and divider */
cfg = readl(base + regs->cfg_rcgr);
cfg &= ~CFG_MASK;
cfg |= source & CFG_CLK_SRC_MASK; /* Select clock source */
/* Set the divider; HW permits fraction dividers (+0.5), but
for simplicity, we will support integers only */
if (div)
cfg |= (2 * div - 1) & CFG_DIVIDER_MASK;
if (n_val)
cfg |= CFG_MODE_DUAL_EDGE;
writel(cfg, base + regs->cfg_rcgr); /* Write new clock configuration */
/* Inform h/w to start using the new config. */
clk_bcr_update(base + regs->cmd_rcgr);
}
static int msm_clk_probe(struct udevice *dev)
{
struct msm_clk_priv *priv = dev_get_priv(dev);
priv->base = devfdt_get_addr(dev);
if (priv->base == FDT_ADDR_T_NONE)
return -EINVAL;
return 0;
}
static ulong msm_clk_set_rate(struct clk *clk, ulong rate)
{
return msm_set_rate(clk, rate);
}
static struct clk_ops msm_clk_ops = {
.set_rate = msm_clk_set_rate,
};
static const struct udevice_id msm_clk_ids[] = {
{ .compatible = "qcom,gcc-msm8916" },
{ .compatible = "qcom,gcc-apq8016" },
{ .compatible = "qcom,gcc-msm8996" },
{ .compatible = "qcom,gcc-apq8096" },
{ }
};
U_BOOT_DRIVER(clk_msm) = {
.name = "clk_msm",
.id = UCLASS_CLK,
.of_match = msm_clk_ids,
.ops = &msm_clk_ops,
.priv_auto_alloc_size = sizeof(struct msm_clk_priv),
.probe = msm_clk_probe,
};