redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

MIPS: ralink: fix cpu clock of mt7621 and add dt clk devices 

For a long time the mt7621 uses a fixed cpu clock which causes a problem
if the cpu frequency is not 880MHz.

This patch fixes the cpu clock calculation and adds the cpu/bus clkdev
which will be used in dts.

Ported from OpenWrt:
c7ca224299 ramips: fix cpu clock of mt7621 and add dt clk devices

Signed-off-by: Weijie Gao <hackpascal@gmail.com>
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: John Crispin <john@phrozen.org>
Cc: linux-kernel@vger.kernel.org
hifive-unleashed-5.2
Chuanhong Guo 2019-03-21 22:42:51 +08:00 committed by Paul Burton
parent e6331a321a
commit e6046b5e69
No known key found for this signature in database
GPG Key ID: 3EA79FACB57500DD
3 changed files with 93 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/mips/include/asm/mach-ralink/mt7621.h
View File

@ -19,6 +19,10 @@
#define SYSC_REG_CHIP_REV 0x0c
#define SYSC_REG_SYSTEM_CONFIG0 0x10
#define SYSC_REG_SYSTEM_CONFIG1 0x14
#define SYSC_REG_CLKCFG0 0x2c
#define SYSC_REG_CUR_CLK_STS 0x44
#define MEMC_REG_CPU_PLL 0x648
#define CHIP_REV_PKG_MASK 0x1
#define CHIP_REV_PKG_SHIFT 16
@ -26,6 +30,22 @@
#define CHIP_REV_VER_SHIFT 8
#define CHIP_REV_ECO_MASK 0xf
#define XTAL_MODE_SEL_MASK 0x7
#define XTAL_MODE_SEL_SHIFT 6
#define CPU_CLK_SEL_MASK 0x3
#define CPU_CLK_SEL_SHIFT 30
#define CUR_CPU_FDIV_MASK 0x1f
#define CUR_CPU_FDIV_SHIFT 8
#define CUR_CPU_FFRAC_MASK 0x1f
#define CUR_CPU_FFRAC_SHIFT 0
#define CPU_PLL_PREDIV_MASK 0x3
#define CPU_PLL_PREDIV_SHIFT 12
#define CPU_PLL_FBDIV_MASK 0x7f
#define CPU_PLL_FBDIV_SHIFT 4
#define MT7621_DRAM_BASE 0x0
#define MT7621_DDR2_SIZE_MIN 32
#define MT7621_DDR2_SIZE_MAX 256

102
arch/mips/ralink/mt7621.c
View File

@ -9,22 +9,22 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <dt-bindings/clock/mt7621-clk.h>
#include <asm/mipsregs.h>
#include <asm/smp-ops.h>
#include <asm/mips-cps.h>
#include <asm/mach-ralink/ralink_regs.h>
#include <asm/mach-ralink/mt7621.h>
#include <asm/time.h>
#include <pinmux.h>
#include "common.h"
#define SYSC_REG_SYSCFG 0x10
#define SYSC_REG_CPLL_CLKCFG0 0x2c
#define SYSC_REG_CUR_CLK_STS 0x44
#define CPU_CLK_SEL (BIT(30) | BIT(31))
#define MT7621_GPIO_MODE_UART1 1
#define MT7621_GPIO_MODE_I2C 2
#define MT7621_GPIO_MODE_UART3_MASK 0x3
@ -110,49 +110,89 @@ static struct rt2880_pmx_group mt7621_pinmux_data[] = {
{ 0 }
};
static struct clk *clks[MT7621_CLK_MAX];
static struct clk_onecell_data clk_data = {
.clks = clks,
.clk_num = ARRAY_SIZE(clks),
};
phys_addr_t mips_cpc_default_phys_base(void)
{
panic("Cannot detect cpc address");
}
static struct clk *__init mt7621_add_sys_clkdev(
const char *id, unsigned long rate)
{
struct clk *clk;
int err;
clk = clk_register_fixed_rate(NULL, id, NULL, 0, rate);
if (IS_ERR(clk))
panic("failed to allocate %s clock structure", id);
err = clk_register_clkdev(clk, id, NULL);
if (err)
panic("unable to register %s clock device", id);
return clk;
}
void __init ralink_clk_init(void)
{
int cpu_fdiv = 0;
int cpu_ffrac = 0;
int fbdiv = 0;
u32 clk_sts, syscfg;
u8 clk_sel = 0, xtal_mode;
u32 cpu_clk;
const static u32 prediv_tbl[] = {0, 1, 2, 2};
u32 syscfg, xtal_sel, clkcfg, clk_sel, curclk, ffiv, ffrac;
u32 pll, prediv, fbdiv;
u32 xtal_clk, cpu_clk, bus_clk;
if ((rt_sysc_r32(SYSC_REG_CPLL_CLKCFG0) & CPU_CLK_SEL) != 0)
clk_sel = 1;
syscfg = rt_sysc_r32(SYSC_REG_SYSTEM_CONFIG0);
xtal_sel = (syscfg >> XTAL_MODE_SEL_SHIFT) & XTAL_MODE_SEL_MASK;
clkcfg = rt_sysc_r32(SYSC_REG_CLKCFG0);
clk_sel = (clkcfg >> CPU_CLK_SEL_SHIFT) & CPU_CLK_SEL_MASK;
curclk = rt_sysc_r32(SYSC_REG_CUR_CLK_STS);
ffiv = (curclk >> CUR_CPU_FDIV_SHIFT) & CUR_CPU_FDIV_MASK;
ffrac = (curclk >> CUR_CPU_FFRAC_SHIFT) & CUR_CPU_FFRAC_MASK;
if (xtal_sel <= 2)
xtal_clk = 20 * 1000 * 1000;
else if (xtal_sel <= 5)
xtal_clk = 40 * 1000 * 1000;
else
xtal_clk = 25 * 1000 * 1000;
switch (clk_sel) {
case 0:
clk_sts = rt_sysc_r32(SYSC_REG_CUR_CLK_STS);
cpu_fdiv = ((clk_sts >> 8) & 0x1F);
cpu_ffrac = (clk_sts & 0x1F);
cpu_clk = (500 * cpu_ffrac / cpu_fdiv) * 1000 * 1000;
cpu_clk = 500 * 1000 * 1000;
break;
case 1:
fbdiv = ((rt_sysc_r32(0x648) >> 4) & 0x7F) + 1;
syscfg = rt_sysc_r32(SYSC_REG_SYSCFG);
xtal_mode = (syscfg >> 6) & 0x7;
if (xtal_mode >= 6) {
/* 25Mhz Xtal */
cpu_clk = 25 * fbdiv * 1000 * 1000;
} else if (xtal_mode >= 3) {
/* 40Mhz Xtal */
cpu_clk = 40 * fbdiv * 1000 * 1000;
} else {
/* 20Mhz Xtal */
cpu_clk = 20 * fbdiv * 1000 * 1000;
}
pll = rt_memc_r32(MEMC_REG_CPU_PLL);
fbdiv = (pll >> CPU_PLL_FBDIV_SHIFT) & CPU_PLL_FBDIV_MASK;
prediv = (pll >> CPU_PLL_PREDIV_SHIFT) & CPU_PLL_PREDIV_MASK;
cpu_clk = ((fbdiv + 1) * xtal_clk) >> prediv_tbl[prediv];
break;
default:
cpu_clk = xtal_clk;
}
cpu_clk = cpu_clk / ffiv * ffrac;
bus_clk = cpu_clk / 4;
clks[MT7621_CLK_CPU] = mt7621_add_sys_clkdev("cpu", cpu_clk);
clks[MT7621_CLK_BUS] = mt7621_add_sys_clkdev("bus", bus_clk);
pr_info("CPU Clock: %dMHz\n", cpu_clk / 1000000);
mips_hpt_frequency = cpu_clk / 2;
}
static void __init mt7621_clocks_init_dt(struct device_node *np)
{
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
}
CLK_OF_DECLARE(mt7621_clk, "mediatek,mt7621-pll", mt7621_clocks_init_dt);
void __init ralink_of_remap(void)
{
rt_sysc_membase = plat_of_remap_node("mtk,mt7621-sysc");

4
arch/mips/ralink/timer-gic.c
View File

@ -11,14 +11,14 @@
#include <linux/of.h>
#include <linux/clk-provider.h>
#include <linux/clocksource.h>
#include <asm/time.h>
#include "common.h"
void __init plat_time_init(void)
{
ralink_of_remap();
ralink_clk_init();
of_clk_init(NULL);
timer_probe();
}