kernel-fxtec-pro1x/arch/arm/mach-imx/clk-pllv2.c
Sascha Hauer 6cc90d6de1 ARM i.MX pllv2: use standard register set unconditionally
The i.MX5 PLL has two different register sets for setting the
rate. One is used for the standard case and and is used for
DVFS. Which one of them is used depends on a hardware input
of the PLL. Current implementation reads back from the hardware
which setting is used. This is bogus: If we ever want to implement
DVFS we have to program both register sets and not only the one
which happens to be used at the moment. For now, just use the
standard register set uncondionally.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
2012-06-04 15:23:41 +02:00

236 lines
5.6 KiB
C

#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <asm/div64.h>
#include "clk.h"
#define to_clk_pllv2(clk) (container_of(clk, struct clk_pllv2, clk))
/* PLL Register Offsets */
#define MXC_PLL_DP_CTL 0x00
#define MXC_PLL_DP_CONFIG 0x04
#define MXC_PLL_DP_OP 0x08
#define MXC_PLL_DP_MFD 0x0C
#define MXC_PLL_DP_MFN 0x10
#define MXC_PLL_DP_MFNMINUS 0x14
#define MXC_PLL_DP_MFNPLUS 0x18
#define MXC_PLL_DP_HFS_OP 0x1C
#define MXC_PLL_DP_HFS_MFD 0x20
#define MXC_PLL_DP_HFS_MFN 0x24
#define MXC_PLL_DP_MFN_TOGC 0x28
#define MXC_PLL_DP_DESTAT 0x2c
/* PLL Register Bit definitions */
#define MXC_PLL_DP_CTL_MUL_CTRL 0x2000
#define MXC_PLL_DP_CTL_DPDCK0_2_EN 0x1000
#define MXC_PLL_DP_CTL_DPDCK0_2_OFFSET 12
#define MXC_PLL_DP_CTL_ADE 0x800
#define MXC_PLL_DP_CTL_REF_CLK_DIV 0x400
#define MXC_PLL_DP_CTL_REF_CLK_SEL_MASK (3 << 8)
#define MXC_PLL_DP_CTL_REF_CLK_SEL_OFFSET 8
#define MXC_PLL_DP_CTL_HFSM 0x80
#define MXC_PLL_DP_CTL_PRE 0x40
#define MXC_PLL_DP_CTL_UPEN 0x20
#define MXC_PLL_DP_CTL_RST 0x10
#define MXC_PLL_DP_CTL_RCP 0x8
#define MXC_PLL_DP_CTL_PLM 0x4
#define MXC_PLL_DP_CTL_BRM0 0x2
#define MXC_PLL_DP_CTL_LRF 0x1
#define MXC_PLL_DP_CONFIG_BIST 0x8
#define MXC_PLL_DP_CONFIG_SJC_CE 0x4
#define MXC_PLL_DP_CONFIG_AREN 0x2
#define MXC_PLL_DP_CONFIG_LDREQ 0x1
#define MXC_PLL_DP_OP_MFI_OFFSET 4
#define MXC_PLL_DP_OP_MFI_MASK (0xF << 4)
#define MXC_PLL_DP_OP_PDF_OFFSET 0
#define MXC_PLL_DP_OP_PDF_MASK 0xF
#define MXC_PLL_DP_MFD_OFFSET 0
#define MXC_PLL_DP_MFD_MASK 0x07FFFFFF
#define MXC_PLL_DP_MFN_OFFSET 0x0
#define MXC_PLL_DP_MFN_MASK 0x07FFFFFF
#define MXC_PLL_DP_MFN_TOGC_TOG_DIS (1 << 17)
#define MXC_PLL_DP_MFN_TOGC_TOG_EN (1 << 16)
#define MXC_PLL_DP_MFN_TOGC_CNT_OFFSET 0x0
#define MXC_PLL_DP_MFN_TOGC_CNT_MASK 0xFFFF
#define MXC_PLL_DP_DESTAT_TOG_SEL (1 << 31)
#define MXC_PLL_DP_DESTAT_MFN 0x07FFFFFF
#define MAX_DPLL_WAIT_TRIES 1000 /* 1000 * udelay(1) = 1ms */
struct clk_pllv2 {
struct clk_hw hw;
void __iomem *base;
};
static unsigned long clk_pllv2_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
long mfi, mfn, mfd, pdf, ref_clk, mfn_abs;
unsigned long dp_op, dp_mfd, dp_mfn, dp_ctl, dbl;
void __iomem *pllbase;
s64 temp;
struct clk_pllv2 *pll = to_clk_pllv2(hw);
pllbase = pll->base;
dp_ctl = __raw_readl(pllbase + MXC_PLL_DP_CTL);
dbl = dp_ctl & MXC_PLL_DP_CTL_DPDCK0_2_EN;
dp_op = __raw_readl(pllbase + MXC_PLL_DP_OP);
dp_mfd = __raw_readl(pllbase + MXC_PLL_DP_MFD);
dp_mfn = __raw_readl(pllbase + MXC_PLL_DP_MFN);
pdf = dp_op & MXC_PLL_DP_OP_PDF_MASK;
mfi = (dp_op & MXC_PLL_DP_OP_MFI_MASK) >> MXC_PLL_DP_OP_MFI_OFFSET;
mfi = (mfi <= 5) ? 5 : mfi;
mfd = dp_mfd & MXC_PLL_DP_MFD_MASK;
mfn = mfn_abs = dp_mfn & MXC_PLL_DP_MFN_MASK;
/* Sign extend to 32-bits */
if (mfn >= 0x04000000) {
mfn |= 0xFC000000;
mfn_abs = -mfn;
}
ref_clk = 2 * parent_rate;
if (dbl != 0)
ref_clk *= 2;
ref_clk /= (pdf + 1);
temp = (u64) ref_clk * mfn_abs;
do_div(temp, mfd + 1);
if (mfn < 0)
temp = -temp;
temp = (ref_clk * mfi) + temp;
return temp;
}
static int clk_pllv2_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_pllv2 *pll = to_clk_pllv2(hw);
u32 reg;
void __iomem *pllbase;
long mfi, pdf, mfn, mfd = 999999;
s64 temp64;
unsigned long quad_parent_rate;
unsigned long dp_ctl;
pllbase = pll->base;
quad_parent_rate = 4 * parent_rate;
pdf = mfi = -1;
while (++pdf < 16 && mfi < 5)
mfi = rate * (pdf+1) / quad_parent_rate;
if (mfi > 15)
return -EINVAL;
pdf--;
temp64 = rate * (pdf+1) - quad_parent_rate * mfi;
do_div(temp64, quad_parent_rate/1000000);
mfn = (long)temp64;
dp_ctl = __raw_readl(pllbase + MXC_PLL_DP_CTL);
/* use dpdck0_2 */
__raw_writel(dp_ctl | 0x1000L, pllbase + MXC_PLL_DP_CTL);
reg = mfi << 4 | pdf;
__raw_writel(reg, pllbase + MXC_PLL_DP_OP);
__raw_writel(mfd, pllbase + MXC_PLL_DP_MFD);
__raw_writel(mfn, pllbase + MXC_PLL_DP_MFN);
return 0;
}
static long clk_pllv2_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
return rate;
}
static int clk_pllv2_prepare(struct clk_hw *hw)
{
struct clk_pllv2 *pll = to_clk_pllv2(hw);
u32 reg;
void __iomem *pllbase;
int i = 0;
pllbase = pll->base;
reg = __raw_readl(pllbase + MXC_PLL_DP_CTL) | MXC_PLL_DP_CTL_UPEN;
__raw_writel(reg, pllbase + MXC_PLL_DP_CTL);
/* Wait for lock */
do {
reg = __raw_readl(pllbase + MXC_PLL_DP_CTL);
if (reg & MXC_PLL_DP_CTL_LRF)
break;
udelay(1);
} while (++i < MAX_DPLL_WAIT_TRIES);
if (i == MAX_DPLL_WAIT_TRIES) {
pr_err("MX5: pll locking failed\n");
return -EINVAL;
}
return 0;
}
static void clk_pllv2_unprepare(struct clk_hw *hw)
{
struct clk_pllv2 *pll = to_clk_pllv2(hw);
u32 reg;
void __iomem *pllbase;
pllbase = pll->base;
reg = __raw_readl(pllbase + MXC_PLL_DP_CTL) & ~MXC_PLL_DP_CTL_UPEN;
__raw_writel(reg, pllbase + MXC_PLL_DP_CTL);
}
struct clk_ops clk_pllv2_ops = {
.prepare = clk_pllv2_prepare,
.unprepare = clk_pllv2_unprepare,
.recalc_rate = clk_pllv2_recalc_rate,
.round_rate = clk_pllv2_round_rate,
.set_rate = clk_pllv2_set_rate,
};
struct clk *imx_clk_pllv2(const char *name, const char *parent,
void __iomem *base)
{
struct clk_pllv2 *pll;
struct clk *clk;
struct clk_init_data init;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
pll->base = base;
init.name = name;
init.ops = &clk_pllv2_ops;
init.flags = 0;
init.parent_names = &parent;
init.num_parents = 1;
pll->hw.init = &init;
clk = clk_register(NULL, &pll->hw);
if (IS_ERR(clk))
kfree(pll);
return clk;
}