u-boot/drivers/clk/mvebu/armada-37xx-tbg.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* Marvell Armada 37xx SoC Time Base Generator clocks
*
* Marek Behun <marek.behun@nic.cz>
*
* Based on Linux driver by:
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*/
#include <common.h>
#include <clk-uclass.h>
#include <clk.h>
#include <dm.h>
#include <asm/io.h>
#include <asm/arch/cpu.h>
#include <dm/device_compat.h>
#define NUM_TBG 4
#define TBG_CTRL0 0x4
#define TBG_CTRL1 0x8
#define TBG_CTRL7 0x20
#define TBG_CTRL8 0x30
#define TBG_DIV_MASK 0x1FF
#define TBG_A_REFDIV 0
#define TBG_B_REFDIV 16
#define TBG_A_FBDIV 2
#define TBG_B_FBDIV 18
#define TBG_A_VCODIV_SE 0
#define TBG_B_VCODIV_SE 16
#define TBG_A_VCODIV_DIFF 1
#define TBG_B_VCODIV_DIFF 17
struct tbg_def {
const char *name;
u32 refdiv_offset;
u32 fbdiv_offset;
u32 vcodiv_reg;
u32 vcodiv_offset;
};
static const struct tbg_def tbg[NUM_TBG] = {
{"TBG-A-P", TBG_A_REFDIV, TBG_A_FBDIV, TBG_CTRL8, TBG_A_VCODIV_DIFF},
{"TBG-B-P", TBG_B_REFDIV, TBG_B_FBDIV, TBG_CTRL8, TBG_B_VCODIV_DIFF},
{"TBG-A-S", TBG_A_REFDIV, TBG_A_FBDIV, TBG_CTRL1, TBG_A_VCODIV_SE},
{"TBG-B-S", TBG_B_REFDIV, TBG_B_FBDIV, TBG_CTRL1, TBG_B_VCODIV_SE},
};
struct a37xx_tbgclk {
ulong rates[NUM_TBG];
unsigned int mult[NUM_TBG];
unsigned int div[NUM_TBG];
};
static unsigned int tbg_get_mult(void __iomem *reg, const struct tbg_def *ptbg)
{
u32 val;
val = readl(reg + TBG_CTRL0);
return ((val >> ptbg->fbdiv_offset) & TBG_DIV_MASK) << 2;
}
static unsigned int tbg_get_div(void __iomem *reg, const struct tbg_def *ptbg)
{
u32 val;
unsigned int div;
val = readl(reg + TBG_CTRL7);
div = (val >> ptbg->refdiv_offset) & TBG_DIV_MASK;
if (div == 0)
div = 1;
val = readl(reg + ptbg->vcodiv_reg);
div *= 1 << ((val >> ptbg->vcodiv_offset) & TBG_DIV_MASK);
return div;
}
static ulong armada_37xx_tbg_clk_get_rate(struct clk *clk)
{
struct a37xx_tbgclk *priv = dev_get_priv(clk->dev);
if (clk->id >= NUM_TBG)
return -ENODEV;
return priv->rates[clk->id];
}
#if defined(CONFIG_CMD_CLK) && defined(CONFIG_CLK_ARMADA_3720)
int armada_37xx_tbg_clk_dump(struct udevice *dev)
{
struct a37xx_tbgclk *priv = dev_get_priv(dev);
int i;
for (i = 0; i < NUM_TBG; ++i)
printf(" %s at %lu Hz\n", tbg[i].name,
priv->rates[i]);
printf("\n");
return 0;
}
#endif
static int armada_37xx_tbg_clk_probe(struct udevice *dev)
{
struct a37xx_tbgclk *priv = dev_get_priv(dev);
void __iomem *reg;
ulong xtal;
int i;
reg = dev_read_addr_ptr(dev);
if (!reg) {
dev_err(dev, "no io address\n");
return -ENODEV;
}
xtal = (ulong)get_ref_clk() * 1000000;
for (i = 0; i < NUM_TBG; ++i) {
unsigned int mult, div;
mult = tbg_get_mult(reg, &tbg[i]);
div = tbg_get_div(reg, &tbg[i]);
priv->rates[i] = (xtal * mult) / div;
}
return 0;
}
static const struct clk_ops armada_37xx_tbg_clk_ops = {
.get_rate = armada_37xx_tbg_clk_get_rate,
};
static const struct udevice_id armada_37xx_tbg_clk_ids[] = {
{ .compatible = "marvell,armada-3700-tbg-clock" },
{}
};
U_BOOT_DRIVER(armada_37xx_tbg_clk) = {
.name = "armada_37xx_tbg_clk",
.id = UCLASS_CLK,
.of_match = armada_37xx_tbg_clk_ids,
.ops = &armada_37xx_tbg_clk_ops,
.priv_auto_alloc_size = sizeof(struct a37xx_tbgclk),
.probe = armada_37xx_tbg_clk_probe,
};