linux/drivers/clk/versatile/clk-realview.c

115 lines
2.8 KiB
C

#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/clk-provider.h>
#include <mach/hardware.h>
#include <mach/platform.h>
#include "clk-icst.h"
/*
* Implementation of the ARM RealView clock trees.
*/
static void __iomem *sys_lock;
static void __iomem *sys_vcoreg;
/**
* realview_oscvco_get() - get ICST OSC settings for the RealView
*/
static struct icst_vco realview_oscvco_get(void)
{
u32 val;
struct icst_vco vco;
val = readl(sys_vcoreg);
vco.v = val & 0x1ff;
vco.r = (val >> 9) & 0x7f;
vco.s = (val >> 16) & 03;
return vco;
}
static void realview_oscvco_set(struct icst_vco vco)
{
u32 val;
val = readl(sys_vcoreg) & ~0x7ffff;
val |= vco.v | (vco.r << 9) | (vco.s << 16);
/* This magic unlocks the CM VCO so it can be controlled */
writel(0xa05f, sys_lock);
writel(val, sys_vcoreg);
/* This locks the CM again */
writel(0, sys_lock);
}
static const struct icst_params realview_oscvco_params = {
.ref = 24000000,
.vco_max = ICST307_VCO_MAX,
.vco_min = ICST307_VCO_MIN,
.vd_min = 4 + 8,
.vd_max = 511 + 8,
.rd_min = 1 + 2,
.rd_max = 127 + 2,
.s2div = icst307_s2div,
.idx2s = icst307_idx2s,
};
static const struct clk_icst_desc __initdata realview_icst_desc = {
.params = &realview_oscvco_params,
.getvco = realview_oscvco_get,
.setvco = realview_oscvco_set,
};
/*
* realview_clk_init() - set up the RealView clock tree
*/
void __init realview_clk_init(void __iomem *sysbase, bool is_pb1176)
{
struct clk *clk;
sys_lock = sysbase + REALVIEW_SYS_LOCK_OFFSET;
if (is_pb1176)
sys_vcoreg = sysbase + REALVIEW_SYS_OSC0_OFFSET;
else
sys_vcoreg = sysbase + REALVIEW_SYS_OSC4_OFFSET;
/* APB clock dummy */
clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0);
clk_register_clkdev(clk, "apb_pclk", NULL);
/* 24 MHz clock */
clk = clk_register_fixed_rate(NULL, "clk24mhz", NULL, CLK_IS_ROOT,
24000000);
clk_register_clkdev(clk, NULL, "dev:uart0");
clk_register_clkdev(clk, NULL, "dev:uart1");
clk_register_clkdev(clk, NULL, "dev:uart2");
clk_register_clkdev(clk, NULL, "fpga:kmi0");
clk_register_clkdev(clk, NULL, "fpga:kmi1");
clk_register_clkdev(clk, NULL, "fpga:mmc0");
clk_register_clkdev(clk, NULL, "dev:ssp0");
if (is_pb1176) {
/*
* UART3 is on the dev chip in PB1176
* UART4 only exists in PB1176
*/
clk_register_clkdev(clk, NULL, "dev:uart3");
clk_register_clkdev(clk, NULL, "dev:uart4");
} else
clk_register_clkdev(clk, NULL, "fpga:uart3");
/* 1 MHz clock */
clk = clk_register_fixed_rate(NULL, "clk1mhz", NULL, CLK_IS_ROOT,
1000000);
clk_register_clkdev(clk, NULL, "sp804");
/* ICST VCO clock */
clk = icst_clk_register(NULL, &realview_icst_desc);
clk_register_clkdev(clk, NULL, "dev:clcd");
clk_register_clkdev(clk, NULL, "issp:clcd");
}