Re: [PATCH v3 06/19] clk: at91: add PMC pll clocks

[boris brezillon <b.brezillon@overkiz.com>]

On 08/10/2013 12:28, Nicolas Ferre wrote:
> On 08/08/2013 08:07, Boris BREZILLON :
>> This patch adds new at91 pll clock implementation using common clk 
>> framework.
>>
>> The pll clock layout describe the PLLX register layout.
>> There are four pll clock layouts:
>> - at91rm9200
>> - at91sam9g20
>> - at91sam9g45
>> - sama5d3
>>
>> PLL clocks are given characteristics:
>> - min/max clock source rate
>> - ranges of valid clock output rates
>> - values to set in out and icpll fields for each supported output range
>>
>> These characteristics are checked during rate change to avoid
>> over/underclocking.
>>
>> These characteristics are described in atmel's SoC datasheet in
>> "Electrical Characteristics" paragraph.
>>
>> Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
>> ---
>>   drivers/clk/at91/Makefile     |    2 +-
>>   drivers/clk/at91/clk-pll.c    |  506 
>> +++++++++++++++++++++++++++++++++++++++++
>>   drivers/clk/at91/clk-plldiv.c |  137 +++++++++++
>>   drivers/clk/at91/pmc.c        |   21 ++
>>   drivers/clk/at91/pmc.h        |   11 +
>>   include/linux/clk/at91_pmc.h  |    2 +
>>   6 files changed, 678 insertions(+), 1 deletion(-)
>>   create mode 100644 drivers/clk/at91/clk-pll.c
>>   create mode 100644 drivers/clk/at91/clk-plldiv.c
>>
>> diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
>> index 44105bd..902bbf1 100644
>> --- a/drivers/clk/at91/Makefile
>> +++ b/drivers/clk/at91/Makefile
>> @@ -3,4 +3,4 @@
>>   #
>>
>>   obj-y += pmc.o
>> -obj-y += clk-main.o
>> +obj-y += clk-main.o clk-pll.o clk-plldiv.o
>> diff --git a/drivers/clk/at91/clk-pll.c b/drivers/clk/at91/clk-pll.c
>> new file mode 100644
>> index 0000000..ce519f2
>> --- /dev/null
>> +++ b/drivers/clk/at91/clk-pll.c
>> @@ -0,0 +1,506 @@
>> +/*
>> + * drivers/clk/at91/clk-pll.c
>> + *
>> + *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + */
>> +
>> +#include <linux/clk-provider.h>
>> +#include <linux/clkdev.h>
>> +#include <linux/clk/at91_pmc.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/io.h>
>> +#include <linux/wait.h>
>> +#include <linux/sched.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irq.h>
>> +
>> +#include "pmc.h"
>> +
>> +struct clk_pll_characteristics {
>> +    struct clk_range input;
>> +    int num_output;
>> +    struct clk_range *output;
>> +    u16 *icpll;
>> +    u8 *out;
>> +};
>> +
>> +struct clk_pll_layout {
>> +    u32 pllr_mask;
>> +    u16 mul_mask;
>> +    u8 mul_shift;
>> +};
>> +
>> +#define to_clk_pll(hw) container_of(hw, struct clk_pll, hw)
>> +
>> +struct clk_pll {
>> +    struct clk_hw hw;
>> +    struct at91_pmc *pmc;
>> +    unsigned int irq;
>> +    wait_queue_head_t wait;
>> +    u8 id;
>> +    u8 div;
>> +    u8 range;
>> +    u16 mul;
>> +    const struct clk_pll_layout *layout;
>> +    const struct clk_pll_characteristics *characteristics;
>> +};
>> +
>> +static irqreturn_t clk_pll_irq_handler(int irq, void *dev_id)
>> +{
>> +    struct clk_pll *pll = (struct clk_pll *)dev_id;
>> +
>> +    wake_up(&pll->wait);
>> +    disable_irq_nosync(pll->irq);
>> +
>> +    return IRQ_HANDLED;
>> +}
>> +
>> +static int clk_pll_prepare(struct clk_hw *hw)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +    struct at91_pmc *pmc = pll->pmc;
>> +
>> +    while (!(pmc_read(pmc, AT91_PMC_SR) & (1 << (1 + pll->id)))) {
>
> Here, we can define a macro for this driver that can take pll->id and 
> give back the mask: it seems to be used frequently in the driver).

Sure, I will define macros and use them appropriately.

>
>> +        enable_irq(pll->irq);
>> +        wait_event(pll->wait,
>> +               pmc_read(pmc, AT91_PMC_SR) & (1 << (1 + pll->id)));
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static int clk_pll_is_ready(struct clk_hw *hw)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +    struct at91_pmc *pmc = pll->pmc;
>> +
>> +    return !!(pmc_read(pmc, AT91_PMC_SR) &
>> +          (1 << (1 + pll->id)));
>> +}
>> +
>> +static void clk_pll_disable(struct clk_hw *hw)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +    struct at91_pmc *pmc = pll->pmc;
>> +    const struct clk_pll_layout *layout = pll->layout;
>> +    int offset = AT91_CKGR_PLLAR + (pll->id * 4);
>
> Here also, a macro can be interesting to retrieve the PLL register 
> address.
>
>> +    u32 tmp = pmc_read(pmc, offset) & ~(layout->pllr_mask);
>
> Well why not just setting MULA/B to 0? I know it is nearly the same 
> but on sama5d3, there is a field that must always be set to 1 (bit 29).

This was here to handle sama5 (and maybe other SoCs I don't recall) 
specific case.
This way (by reading the PLLR register and masking it with ~pllr_mask) 
the bit that must be set 1 is always set correctly.

How would you do it (handle sama5 specific behaviour) ?

>
>
>> +
>> +    pmc_write(pmc, offset, tmp);
>> +}
>> +
>> +static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
>> +                     unsigned long parent_rate)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +    const struct clk_pll_layout *layout = pll->layout;
>> +    struct at91_pmc *pmc = pll->pmc;
>> +    int offset = AT91_CKGR_PLLAR + (pll->id * 4);
>
> Ditto
>
>> +    u32 tmp = pmc_read(pmc, offset) & layout->pllr_mask;
>> +    u8 div = tmp & 0xFF;
>
> A #defined value, please
>
>> +    u16 mul = (tmp >> layout->mul_shift) & layout->mul_mask;
>> +    if (!div || !mul)
>> +        return 0;
>> +
>> +    return (parent_rate * (mul + 1)) / div;
>> +}
>> +
>> +static long clk_pll_get_best_div_mul(struct clk_pll *pll, unsigned 
>> long rate,
>> +                     unsigned long parent_rate,
>> +                     u32 *div, u32 *mul,
>> +                     u32 *index) {
>> +    unsigned long maxrate;
>> +    unsigned long minrate;
>> +    unsigned long divrate;
>> +    unsigned long bestdiv = 1;
>> +    unsigned long bestmul;
>> +    unsigned long tmpdiv;
>> +    unsigned long roundup;
>> +    unsigned long rounddown;
>> +    unsigned long remainder;
>> +    unsigned long bestremainder;
>> +    unsigned long maxmul;
>> +    unsigned long maxdiv;
>> +    unsigned long mindiv;
>> +    int i = 0;
>> +    const struct clk_pll_layout *layout = pll->layout;
>> +    const struct clk_pll_characteristics *characteristics =
>> +                            pll->characteristics;
>> +
>> +    /* Minimum divider = 1 */
>> +    /* Maximum multiplier = max_mul */
>> +    maxmul = layout->mul_mask + 1;
>> +    maxrate = (parent_rate * maxmul) / 1;
>> +
>> +    /* Maximum divider = max_div */
>> +    /* Minimum multiplier = 2 */
>> +    maxdiv = 0xFF;
>
> Same defined value as above
>
>> +    minrate = (parent_rate * 2) / maxdiv;
>> +
>> +    if (parent_rate < characteristics->input.min ||
>> +        parent_rate < characteristics->input.max)
>> +        return -ERANGE;
>> +
>> +    if (parent_rate < minrate || parent_rate > maxrate)
>> +        return -ERANGE;
>> +
>> +    for (i = 0; i < characteristics->num_output; ++i) {
>> +        if (parent_rate >= characteristics->output[i].min &&
>> +            parent_rate <= characteristics->output[i].max)
>> +            break;
>> +        ++i;
>
> another iteration of "i" in the loop? If it is required, consider 
> using the for() loop with i += 2...

This is not required: this is a bug. I'll fix it.
>
>> +    }
>> +
>> +    if (i >= characteristics->num_output)
>> +        return -ERANGE;
>> +
>> +    bestmul = rate / parent_rate;
>> +    rounddown = parent_rate % rate;
>> +    roundup = rate - rounddown;
>> +    bestremainder = roundup < rounddown ? roundup : rounddown;
>> +
>> +    if (!bestremainder) {
>> +        if (div)
>> +            *div = bestdiv;
>> +        if (mul)
>> +            *mul = bestmul;
>> +        if (index)
>> +            *index = i;
>> +        return rate;
>> +    }
>> +
>> +    maxdiv = 255 / (bestmul + 1);
>> +    if (parent_rate / maxdiv < characteristics->input.min)
>> +        maxdiv = parent_rate / characteristics->input.min;
>> +    mindiv = parent_rate / characteristics->input.max;
>> +    if (parent_rate % characteristics->input.max)
>> +        mindiv++;
>> +
>> +    for (tmpdiv = mindiv; tmpdiv < maxdiv; tmpdiv++) {
>> +        divrate = parent_rate / tmpdiv;
>> +
>> +        rounddown = rate % divrate;
>> +        roundup = divrate - rounddown;
>> +        remainder = roundup < rounddown ? roundup : rounddown;
>> +
>> +        if (remainder < bestremainder) {
>> +            bestremainder = remainder;
>> +            bestmul = rate / divrate;
>> +            bestdiv = tmpdiv;
>> +        }
>> +
>> +        if (!remainder)
>> +            break;
>> +    }
>> +
>> +    rate = (parent_rate / bestdiv) * bestmul;
>> +
>> +    if (div)
>> +        *div = bestdiv;
>> +    if (mul)
>> +        *mul = bestmul;
>> +    if (index)
>> +        *index = i;
>> +
>> +    return rate;
>> +}
>> +
>> +static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
>> +                    unsigned long *parent_rate)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +
>> +    return clk_pll_get_best_div_mul(pll, rate, *parent_rate,
>> +                    NULL, NULL, NULL);
>> +
>> +}
>> +
>> +static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
>> +                unsigned long parent_rate)
>> +{
>> +    struct clk_pll *pll = to_clk_pll(hw);
>> +    struct at91_pmc *pmc = pll->pmc;
>> +    const struct clk_pll_layout *layout = pll->layout;
>> +    const struct clk_pll_characteristics *characteristics =
>> +                        pll->characteristics;
>> +    int offset = AT91_CKGR_PLLAR + (pll->id * 4);
>
> Ditto
>
>> +    long ret;
>> +    u32 div;
>> +    u32 mul;
>> +    u32 index;
>> +    u32 tmp;
>> +    u8 out = 0;
>> +
>> +    ret = clk_pll_get_best_div_mul(pll, rate, parent_rate,
>> +                       &div, &mul, &index);
>> +    if (ret < 0)
>> +        return ret;
>> +
>> +    if (characteristics->out)
>> +        out = characteristics->out[pll->range];
>> +    if (characteristics->icpll) {
>> +        tmp = pmc_read(pmc, AT91_PMC_PLLICPR) &
>> +              ~(0xFFFF << (16 * pll->id));
>
> Macros and defined values, please
>
>> +        tmp |= characteristics->icpll[pll->range] << (16 * pll->id);
>
> Here also
>
>> +        pmc_write(pmc, AT91_PMC_PLLICPR, tmp);
>> +    }
>> +    tmp = pmc_read(pmc, offset) & ~(layout->pllr_mask);
>> +    tmp |= layout->pllr_mask & (div | 0x3F << 8 | out << 14 |
>> +                    (mul & layout->mul_mask) <<
>> +                    layout->mul_shift);
>
> Here also
>
>> +    pmc_write(pmc, offset, tmp);

I realize there is a bug here:
  - pll->div and ->mul are never set
  - we should not write the new conf to the PLLR/ICPPL registers (this 
should be done in clk_prepare)

I'll fix it.

>> +
>> +    return 0;
>> +}
>> +
>> +static const struct clk_ops pll_ops = {
>> +    .prepare = clk_pll_prepare,
>> +    .is_prepared = clk_pll_is_ready,
>> +    .disable = clk_pll_disable,
>> +    .is_enabled = clk_pll_is_ready,
>> +    .recalc_rate = clk_pll_recalc_rate,
>> +    .round_rate = clk_pll_round_rate,
>> +    .set_rate = clk_pll_set_rate,
>> +};
>> +
>> +static struct clk * __init
>> +at91_clk_register_pll(struct at91_pmc *pmc, unsigned int irq, const 
>> char *name,
>> +              const char *parent_name, u8 id,
>> +              const struct clk_pll_layout *layout,
>> +              const struct clk_pll_characteristics *characteristics)
>> +{
>> +    struct clk_pll *pll;
>> +    struct clk *clk = NULL;
>> +    struct clk_init_data init;
>> +    int ret;
>> +
>> +    id &= 3;
>
> defined value please
>
>> +
>> +    pll = kzalloc(sizeof(*pll), GFP_KERNEL);
>> +    if (!pll)
>> +        return ERR_PTR(-ENOMEM);
>> +
>> +    init.name = name;
>> +    init.ops = &pll_ops;
>> +    init.parent_names = &parent_name;
>> +    init.num_parents = 1;
>> +    init.flags = CLK_SET_RATE_GATE;
>> +
>> +    pll->id = id;
>> +    pll->hw.init = &init;
>> +    pll->layout = layout;
>> +    pll->characteristics = characteristics;
>> +    pll->pmc = pmc;
>> +    pll->irq = irq;
>> +    init_waitqueue_head(&pll->wait);
>> +    irq_set_status_flags(pll->irq, IRQ_NOAUTOEN);
>> +    ret = request_irq(pll->irq, clk_pll_irq_handler, IRQF_TRIGGER_HIGH,
>> +              id ? "clk-pllb" : "clk-plla", pll);
>> +    if (ret)
>> +        return ERR_PTR(ret);
>> +
>> +    clk = clk_register(NULL, &pll->hw);
>> +
>
> No extra space
I'll remove all unneeded spaces and/or blank lines.
>
>> +    if (IS_ERR(clk))
>> +        kfree(pll);
>> +
>> +    return clk;
>> +}
>> +
>> +
>> +static const struct clk_pll_layout at91rm9200_pll_layout = {
>> +    .pllr_mask = 0x7FFFFFF,
>> +    .mul_shift = 16,
>> +    .mul_mask = 0x7FF,
>> +};
>> +
>> +static const struct clk_pll_layout at91sam9g45_pll_layout = {
>> +    .pllr_mask = 0xFFFFFF,
>> +    .mul_shift = 16,
>> +    .mul_mask = 0xFF,
>> +};
>> +
>> +static const struct clk_pll_layout at91sam9g20_pllb_layout = {
>> +    .pllr_mask = 0x3FFFFF,
>> +    .mul_shift = 16,
>> +    .mul_mask = 0x3F,
>> +};
>> +
>> +static const struct clk_pll_layout sama5d3_pll_layout = {
>> +    .pllr_mask = 0x1FFFFFF,
>> +    .mul_shift = 18,
>> +    .mul_mask = 0x7F,
>> +};
>> +
>> +
>> +static struct clk_pll_characteristics * __init
>> +of_at91_clk_pll_get_characteristics(struct device_node *np)
>> +{
>> +    int i;
>> +    int offset;
>> +    u32 tmp;
>> +    int num_output;
>> +    u32 num_cells;
>> +    struct clk_range input;
>> +    struct clk_range *output;
>> +    u8 *out = NULL;
>> +    u16 *icpll = NULL;
>> +    struct clk_pll_characteristics *characteristics;
>> +
>> +    if (of_property_read_u32_index(np, "atmel,clk-input-range", 0, 
>> &tmp))
>> +        return NULL;
>> +    input.min = tmp;
>> +
>> +    if (of_property_read_u32_index(np, "atmel,clk-input-range", 1, 
>> &tmp))
>> +        return NULL;
>> +    input.max = tmp;
>> +
>> +    if (of_property_read_u32(np, "#atmel,pll-clk-output-range-cells",
>> +                 &num_cells))
>> +        return NULL;
>> +
>> +    if (num_cells < 2 || num_cells > 4)
>> +        return NULL;
>> +
>> +    if (!of_get_property(np, "atmel,pll-clk-output-ranges", &tmp))
>> +        return NULL;
>> +    num_output = tmp / (sizeof(u32) * num_cells);
>> +
>> +    characteristics = kzalloc(sizeof(*characteristics), GFP_KERNEL);
>> +    if (!characteristics)
>> +        return NULL;
>> +
>> +    output = kzalloc(sizeof(*output) * num_output, GFP_KERNEL);
>> +    if (!output)
>> +        goto out_free_characteristics;
>> +
>> +    if (num_cells > 2) {
>> +        out = kzalloc(sizeof(*out) * num_output, GFP_KERNEL);
>> +        if (!out)
>> +            goto out_free_output;
>> +    }
>> +
>> +    if (num_cells > 3) {
>> +        icpll = kzalloc(sizeof(*icpll) * num_output, GFP_KERNEL);
>> +        if (!icpll)
>> +            goto out_free_output;
>> +    }
>> +
>> +    for (i = 0; i < num_output; i++) {
>> +        offset = i * num_cells;
>> +        if (of_property_read_u32_index(np,
>> +                           "atmel,pll-clk-output-ranges",
>> +                           offset, &tmp))
>> +            goto out_free_output;
>> +        output[i].min = tmp;
>> +        if (of_property_read_u32_index(np,
>> +                           "atmel,pll-clk-output-ranges",
>> +                           offset + 1, &tmp))
>> +            goto out_free_output;
>> +        output[i].max = tmp;
>> +
>> +        if (num_cells == 2)
>> +            continue;
>> +
>> +        if (of_property_read_u32_index(np,
>> +                           "atmel,pll-clk-output-ranges",
>> +                           offset + 2, &tmp))
>> +            goto out_free_output;
>> +        out[i] = tmp;
>> +
>> +        if (num_cells == 3)
>> +            continue;
>> +
>> +        if (of_property_read_u32_index(np,
>> +                           "atmel,pll-clk-output-ranges",
>> +                           offset + 3, &tmp))
>> +            goto out_free_output;
>> +        icpll[i] = tmp;
>> +    }
>> +
>> +    characteristics->input = input;
>> +    characteristics->num_output = num_output;
>> +    characteristics->output = output;
>> +    characteristics->out = out;
>> +    characteristics->icpll = icpll;
>> +    return characteristics;
>> +
>> +out_free_output:
>> +    kfree(icpll);
>> +    kfree(out);
>> +    kfree(output);
>> +out_free_characteristics:
>> +    kfree(characteristics);
>> +    return NULL;
>> +}
>> +
>> +static void __init
>> +of_at91_clk_pll_setup(struct device_node *np, struct at91_pmc *pmc,
>> +              const struct clk_pll_layout *layout)
>> +{
>> +    u32 id;
>> +    unsigned int irq;
>> +    struct clk *clk;
>> +    const char *parent_name;
>> +    const char *name = np->name;
>> +    struct clk_pll_characteristics *characteristics;
>> +
>> +    if (of_property_read_u32(np, "atmel,clk-id", &id))
>> +        return;
>> +
>> +    parent_name = of_clk_get_parent_name(np, 0);
>> +
>> +    of_property_read_string(np, "clock-output-names", &name);
>> +
>> +    characteristics = of_at91_clk_pll_get_characteristics(np);
>> +    if (!characteristics)
>> +        return;
>> +
>> +    irq = irq_of_parse_and_map(np, 0);
>> +    if (!irq)
>> +        return;
>> +
>> +    clk = at91_clk_register_pll(pmc, irq, name, parent_name, id, 
>> layout,
>> +                    characteristics);
>> +
>
> No extra white line
>
>> +    if (IS_ERR(clk))
>> +        goto out_free_characteristics;
>> +
>> +    of_clk_add_provider(np, of_clk_src_simple_get, clk);
>> +    return;
>> +
>> +out_free_characteristics:
>> +    kfree(characteristics);
>> +}
>> +
>> +void __init of_at91rm9200_clk_pll_setup(struct device_node *np,
>> +                           struct at91_pmc *pmc)
>> +{
>> +    of_at91_clk_pll_setup(np, pmc, &at91rm9200_pll_layout);
>> +}
>> +
>> +void __init of_at91sam9g45_clk_pll_setup(struct device_node *np,
>> +                        struct at91_pmc *pmc)
>> +{
>> +    of_at91_clk_pll_setup(np, pmc, &at91sam9g45_pll_layout);
>> +}
>> +
>> +void __init of_at91sam9g20_clk_pllb_setup(struct device_node *np,
>> +                         struct at91_pmc *pmc)
>> +{
>> +    of_at91_clk_pll_setup(np, pmc, &at91sam9g20_pllb_layout);
>> +}
>> +
>> +void __init of_sama5d3_clk_pll_setup(struct device_node *np,
>> +                        struct at91_pmc *pmc)
>> +{
>> +    of_at91_clk_pll_setup(np, pmc, &sama5d3_pll_layout);
>> +}
>> diff --git a/drivers/clk/at91/clk-plldiv.c 
>> b/drivers/clk/at91/clk-plldiv.c
>> new file mode 100644
>> index 0000000..2bbb22b
>> --- /dev/null
>> +++ b/drivers/clk/at91/clk-plldiv.c
>> @@ -0,0 +1,137 @@
>> +/*
>> + * drivers/clk/at91/clk-plldiv.c
>> + *
>> + *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + */
>> +
>> +#include <linux/clk-provider.h>
>> +#include <linux/clkdev.h>
>> +#include <linux/clk/at91_pmc.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/io.h>
>> +
>> +#include "pmc.h"
>> +
>> +#define to_clk_plldiv(hw) container_of(hw, struct clk_plldiv, hw)
>> +
>> +struct clk_plldiv {
>> +    struct clk_hw hw;
>> +    struct at91_pmc *pmc;
>> +};
>> +
>> +static unsigned long clk_plldiv_recalc_rate(struct clk_hw *hw,
>> +                        unsigned long parent_rate)
>> +{
>> +    struct clk_plldiv *plldiv = to_clk_plldiv(hw);
>> +    struct at91_pmc *pmc = plldiv->pmc;
>> +
>> +    if (pmc_read(pmc, AT91_PMC_MCKR) & AT91_PMC_PLLADIV2)
>> +        return parent_rate / 2;
>> +
>> +    return parent_rate;
>> +}
>> +
>> +static long clk_plldiv_round_rate(struct clk_hw *hw, unsigned long 
>> rate,
>> +                    unsigned long *parent_rate)
>> +{
>> +    unsigned long div;
>> +
>> +    if (rate > *parent_rate)
>> +        return *parent_rate;
>> +    div = *parent_rate / 2;
>> +    if (rate < div)
>> +        return div;
>> +
>> +    if (rate - div < *parent_rate - rate)
>> +        return div;
>> +
>> +    return *parent_rate;
>> +}
>> +
>> +static int clk_plldiv_set_rate(struct clk_hw *hw, unsigned long rate,
>> +                   unsigned long parent_rate)
>> +{
>> +    struct clk_plldiv *plldiv = to_clk_plldiv(hw);
>> +    struct at91_pmc *pmc = plldiv->pmc;
>> +    u32 tmp;
>> +
>> +    if (parent_rate != rate && (parent_rate / 2) != rate)
>> +        return -EINVAL;
>> +
>> +    pmc_lock(pmc);
>> +    tmp = pmc_read(pmc, AT91_PMC_MCKR) & ~AT91_PMC_PLLADIV2;
>> +    if ((parent_rate / 2) == rate)
>> +        tmp |= AT91_PMC_PLLADIV2;
>> +    pmc_write(pmc, AT91_PMC_MCKR, tmp);
>> +    pmc_unlock(pmc);
>> +
>> +    return 0;
>> +}
>> +
>> +static const struct clk_ops plldiv_ops = {
>> +    .recalc_rate = clk_plldiv_recalc_rate,
>> +    .round_rate = clk_plldiv_round_rate,
>> +    .set_rate = clk_plldiv_set_rate,
>> +};
>> +
>> +static struct clk * __init
>> +at91_clk_register_plldiv(struct at91_pmc *pmc, const char *name,
>> +             const char *parent_name)
>> +{
>> +    struct clk_plldiv *plldiv;
>> +    struct clk *clk = NULL;
>> +    struct clk_init_data init;
>> +
>> +    plldiv = kzalloc(sizeof(*plldiv), GFP_KERNEL);
>> +    if (!plldiv)
>> +        return ERR_PTR(-ENOMEM);
>> +
>> +    init.name = name;
>> +    init.ops = &plldiv_ops;
>> +    init.parent_names = parent_name ? &parent_name : NULL;
>> +    init.num_parents = parent_name ? 1 : 0;
>> +    init.flags = CLK_SET_RATE_GATE;
>> +
>> +    plldiv->hw.init = &init;
>> +    plldiv->pmc = pmc;
>> +
>> +    clk = clk_register(NULL, &plldiv->hw);
>> +
>> +    if (IS_ERR(clk))
>> +        kfree(plldiv);
>> +
>> +    return clk;
>> +}
>> +
>> +static void __init
>> +of_at91_clk_plldiv_setup(struct device_node *np, struct at91_pmc *pmc)
>> +{
>> +    struct clk *clk;
>> +    const char *parent_name;
>> +    const char *name = np->name;
>> +
>> +    parent_name = of_clk_get_parent_name(np, 0);
>> +
>> +    of_property_read_string(np, "clock-output-names", &name);
>> +
>> +    clk = at91_clk_register_plldiv(pmc, name, parent_name);
>> +
>> +    if (IS_ERR(clk))
>> +        return;
>> +
>> +    of_clk_add_provider(np, of_clk_src_simple_get, clk);
>> +    return;
>> +}
>> +
>> +void __init of_at91sam9x5_clk_plldiv_setup(struct device_node *np,
>> +                       struct at91_pmc *pmc)
>> +{
>> +    of_at91_clk_plldiv_setup(np, pmc);
>> +}
>> diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
>> index 42f0c19..47aff40 100644
>> --- a/drivers/clk/at91/pmc.c
>> +++ b/drivers/clk/at91/pmc.c
>> @@ -221,6 +221,27 @@ static const struct of_device_id pmc_clk_ids[] 
>> __initdata = {
>>           .compatible = "atmel,at91rm9200-clk-main",
>>           .data = of_at91rm9200_clk_main_setup
>>       },
>> +    /* PLL clocks */
>> +    {
>> +        .compatible = "atmel,at91rm9200-clk-pll",
>> +        .data = of_at91rm9200_clk_pll_setup,
>> +    },
>> +    {
>> +        .compatible = "atmel,at91sam9g45-clk-pll",
>> +        .data = of_at91sam9g45_clk_pll_setup,
>> +    },
>> +    {
>> +        .compatible = "atmel,at91sam9g20-clk-pllb",
>> +        .data = of_at91sam9g20_clk_pllb_setup,
>> +    },
>> +    {
>> +        .compatible = "atmel,sama5d3-clk-pll",
>> +        .data = of_sama5d3_clk_pll_setup,
>> +    },
>> +    {
>> +        .compatible = "atmel,at91sam9x5-clk-plldiv",
>> +        .data = of_at91sam9x5_clk_plldiv_setup,
>> +    },
>>       { /*sentinel*/ }
>>   };
>>
>> diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
>> index 294e230..35ccbbc 100644
>> --- a/drivers/clk/at91/pmc.h
>> +++ b/drivers/clk/at91/pmc.h
>> @@ -58,4 +58,15 @@ static inline void pmc_write(struct at91_pmc *pmc, 
>> int offset, u32 value)
>>   extern void __init of_at91rm9200_clk_main_setup(struct device_node 
>> *np,
>>                           struct at91_pmc *pmc);
>>
>> +extern void __init of_at91rm9200_clk_pll_setup(struct device_node *np,
>> +                           struct at91_pmc *pmc);
>> +extern void __init of_at91sam9g45_clk_pll_setup(struct device_node *np,
>> +                        struct at91_pmc *pmc);
>> +extern void __init of_at91sam9g20_clk_pllb_setup(struct device_node 
>> *np,
>> +                         struct at91_pmc *pmc);
>> +extern void __init of_sama5d3_clk_pll_setup(struct device_node *np,
>> +                        struct at91_pmc *pmc);
>> +extern void __init of_at91sam9x5_clk_plldiv_setup(struct device_node 
>> *np,
>> +                          struct at91_pmc *pmc);
>> +
>>   #endif /* __PMC_H_ */
>> diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
>> index 00c45b3..a6911eb 100644
>> --- a/include/linux/clk/at91_pmc.h
>> +++ b/include/linux/clk/at91_pmc.h
>> @@ -164,6 +164,8 @@ extern void __iomem *at91_pmc_base;
>>   #define        AT91_PMC_CFDEV        (1 << 18)        /* Clock 
>> Failure Detector Event [some SAM9] */
>>   #define    AT91_PMC_IMR        0x6c            /* Interrupt Mask 
>> Register */
>>
>> +#define AT91_PMC_PLLICPR    0x80            /* PLL Charge Pump 
>> Current Register */
>> +
>>   #define AT91_PMC_PROT        0xe4            /* Write Protect Mode 
>> Register [some SAM9] */
>>   #define        AT91_PMC_WPEN        (0x1  <<  0) /* Write Protect 
>> Enable */
>>   #define        AT91_PMC_WPKEY        (0xffffff << 8)        /* 
>> Write Protect Key */
>>
>
>