linux_old1/drivers/clk/at91/clk-programmable.c

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/*
* 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 <linux/wait.h>
#include <linux/sched.h>
#include "pmc.h"
#define PROG_SOURCE_MAX 5
#define PROG_ID_MAX 7
#define PROG_STATUS_MASK(id) (1 << ((id) + 8))
#define PROG_PRES_MASK 0x7
#define PROG_MAX_RM9200_CSS 3
struct clk_programmable_layout {
u8 pres_shift;
u8 css_mask;
u8 have_slck_mck;
};
struct clk_programmable {
struct clk_hw hw;
struct at91_pmc *pmc;
u8 id;
const struct clk_programmable_layout *layout;
};
#define to_clk_programmable(hw) container_of(hw, struct clk_programmable, hw)
static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
u32 pres;
struct clk_programmable *prog = to_clk_programmable(hw);
struct at91_pmc *pmc = prog->pmc;
const struct clk_programmable_layout *layout = prog->layout;
pres = (pmc_read(pmc, AT91_PMC_PCKR(prog->id)) >> layout->pres_shift) &
PROG_PRES_MASK;
return parent_rate >> pres;
}
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
static int clk_programmable_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct clk *parent = NULL;
long best_rate = -EINVAL;
unsigned long parent_rate;
unsigned long tmp_rate;
int shift;
int i;
for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
parent = clk_get_parent_by_index(hw->clk, i);
if (!parent)
continue;
parent_rate = __clk_get_rate(parent);
for (shift = 0; shift < PROG_PRES_MASK; shift++) {
tmp_rate = parent_rate >> shift;
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
if (tmp_rate <= req->rate)
break;
}
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
if (tmp_rate > req->rate)
continue;
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
if (best_rate < 0 ||
(req->rate - tmp_rate) < (req->rate - best_rate)) {
best_rate = tmp_rate;
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
req->best_parent_rate = parent_rate;
req->best_parent_hw = __clk_get_hw(parent);
}
if (!best_rate)
break;
}
clk: change clk_ops' ->determine_rate() prototype Clock rates are stored in an unsigned long field, but ->determine_rate() (which returns a rounded rate from a requested one) returns a long value (errors are reported using negative error codes), which can lead to long overflow if the clock rate exceed 2Ghz. Change ->determine_rate() prototype to return 0 or an error code, and pass a pointer to a clk_rate_request structure containing the expected target rate and the rate constraints imposed by clk users. The clk_rate_request structure might be extended in the future to contain other kind of constraints like the rounding policy, the maximum clock inaccuracy or other things that are not yet supported by the CCF (power consumption constraints ?). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> CC: Jonathan Corbet <corbet@lwn.net> CC: Tony Lindgren <tony@atomide.com> CC: Ralf Baechle <ralf@linux-mips.org> CC: "Emilio López" <emilio@elopez.com.ar> CC: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Tero Kristo <t-kristo@ti.com> CC: Peter De Schrijver <pdeschrijver@nvidia.com> CC: Prashant Gaikwad <pgaikwad@nvidia.com> CC: Stephen Warren <swarren@wwwdotorg.org> CC: Thierry Reding <thierry.reding@gmail.com> CC: Alexandre Courbot <gnurou@gmail.com> CC: linux-doc@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-omap@vger.kernel.org CC: linux-mips@linux-mips.org CC: linux-tegra@vger.kernel.org [sboyd@codeaurora.org: Fix parent dereference problem in __clk_determine_rate()] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> [sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate clocks without parents or a rate determining op] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-08 02:48:08 +08:00
if (best_rate < 0)
return best_rate;
req->rate = best_rate;
return 0;
}
static int clk_programmable_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_programmable *prog = to_clk_programmable(hw);
const struct clk_programmable_layout *layout = prog->layout;
struct at91_pmc *pmc = prog->pmc;
u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) & ~layout->css_mask;
if (layout->have_slck_mck)
tmp &= AT91_PMC_CSSMCK_MCK;
if (index > layout->css_mask) {
if (index > PROG_MAX_RM9200_CSS && layout->have_slck_mck) {
tmp |= AT91_PMC_CSSMCK_MCK;
return 0;
} else {
return -EINVAL;
}
}
pmc_write(pmc, AT91_PMC_PCKR(prog->id), tmp | index);
return 0;
}
static u8 clk_programmable_get_parent(struct clk_hw *hw)
{
u32 tmp;
u8 ret;
struct clk_programmable *prog = to_clk_programmable(hw);
struct at91_pmc *pmc = prog->pmc;
const struct clk_programmable_layout *layout = prog->layout;
tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id));
ret = tmp & layout->css_mask;
if (layout->have_slck_mck && (tmp & AT91_PMC_CSSMCK_MCK) && !ret)
ret = PROG_MAX_RM9200_CSS + 1;
return ret;
}
static int clk_programmable_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_programmable *prog = to_clk_programmable(hw);
struct at91_pmc *pmc = prog->pmc;
const struct clk_programmable_layout *layout = prog->layout;
unsigned long div = parent_rate / rate;
int shift = 0;
u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) &
~(PROG_PRES_MASK << layout->pres_shift);
if (!div)
return -EINVAL;
shift = fls(div) - 1;
if (div != (1<<shift))
return -EINVAL;
if (shift >= PROG_PRES_MASK)
return -EINVAL;
pmc_write(pmc, AT91_PMC_PCKR(prog->id),
tmp | (shift << layout->pres_shift));
return 0;
}
static const struct clk_ops programmable_ops = {
.recalc_rate = clk_programmable_recalc_rate,
.determine_rate = clk_programmable_determine_rate,
.get_parent = clk_programmable_get_parent,
.set_parent = clk_programmable_set_parent,
.set_rate = clk_programmable_set_rate,
};
static struct clk * __init
at91_clk_register_programmable(struct at91_pmc *pmc,
const char *name, const char **parent_names,
u8 num_parents, u8 id,
const struct clk_programmable_layout *layout)
{
struct clk_programmable *prog;
struct clk *clk = NULL;
struct clk_init_data init;
if (id > PROG_ID_MAX)
return ERR_PTR(-EINVAL);
prog = kzalloc(sizeof(*prog), GFP_KERNEL);
if (!prog)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &programmable_ops;
init.parent_names = parent_names;
init.num_parents = num_parents;
init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
prog->id = id;
prog->layout = layout;
prog->hw.init = &init;
prog->pmc = pmc;
clk = clk_register(NULL, &prog->hw);
if (IS_ERR(clk))
kfree(prog);
return clk;
}
static const struct clk_programmable_layout at91rm9200_programmable_layout = {
.pres_shift = 2,
.css_mask = 0x3,
.have_slck_mck = 0,
};
static const struct clk_programmable_layout at91sam9g45_programmable_layout = {
.pres_shift = 2,
.css_mask = 0x3,
.have_slck_mck = 1,
};
static const struct clk_programmable_layout at91sam9x5_programmable_layout = {
.pres_shift = 4,
.css_mask = 0x7,
.have_slck_mck = 0,
};
static void __init
of_at91_clk_prog_setup(struct device_node *np, struct at91_pmc *pmc,
const struct clk_programmable_layout *layout)
{
int num;
u32 id;
struct clk *clk;
int num_parents;
const char *parent_names[PROG_SOURCE_MAX];
const char *name;
struct device_node *progclknp;
num_parents = of_clk_get_parent_count(np);
if (num_parents <= 0 || num_parents > PROG_SOURCE_MAX)
return;
of_clk_parent_fill(np, parent_names, num_parents);
num = of_get_child_count(np);
if (!num || num > (PROG_ID_MAX + 1))
return;
for_each_child_of_node(np, progclknp) {
if (of_property_read_u32(progclknp, "reg", &id))
continue;
if (of_property_read_string(np, "clock-output-names", &name))
name = progclknp->name;
clk = at91_clk_register_programmable(pmc, name,
parent_names, num_parents,
id, layout);
if (IS_ERR(clk))
continue;
of_clk_add_provider(progclknp, of_clk_src_simple_get, clk);
}
}
void __init of_at91rm9200_clk_prog_setup(struct device_node *np,
struct at91_pmc *pmc)
{
of_at91_clk_prog_setup(np, pmc, &at91rm9200_programmable_layout);
}
void __init of_at91sam9g45_clk_prog_setup(struct device_node *np,
struct at91_pmc *pmc)
{
of_at91_clk_prog_setup(np, pmc, &at91sam9g45_programmable_layout);
}
void __init of_at91sam9x5_clk_prog_setup(struct device_node *np,
struct at91_pmc *pmc)
{
of_at91_clk_prog_setup(np, pmc, &at91sam9x5_programmable_layout);
}