diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-23 18:36:55 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-23 18:36:55 -0800 |
commit | f2c73464d7b399cf4e0c601c1c7d7b079080fa52 (patch) | |
tree | 902decd0c280757075bce5068fee679e0ccc261e /drivers/clk/at91/clk-programmable.c | |
parent | 93abdb7785503c269e73e811f3c7fd23a9243b14 (diff) | |
parent | 273c2279ca502267fac40bcaecb35942380c429c (diff) |
Merge tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Olof Johansson:
"This is the branch where we usually queue up cleanup efforts, moving
drivers out of the architecture directory, header file restructuring,
etc. Sometimes they tangle with new development so it's hard to keep
it strictly to cleanups.
Some of the things included in this branch are:
* Atmel SAMA5 conversion to common clock
* Reset framework conversion for tegra platforms
- Some of this depends on tegra clock driver reworks that are shared
with Mike Turquette's clk tree.
* Tegra DMA refactoring, which are shared branches with the DMA tree.
* Removal of some header files on exynos to prepare for
multiplatform"
* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (169 commits)
ARM: mvebu: move Armada 370/XP specific definitions to armada-370-xp.h
ARM: mvebu: remove prototypes of non-existing functions from common.h
ARM: mvebu: move ARMADA_XP_MAX_CPUS to armada-370-xp.h
serial: sh-sci: Rework baud rate calculation
serial: sh-sci: Compute overrun_bit without using baud rate algo
serial: sh-sci: Remove unused GPIO request code
serial: sh-sci: Move overrun_bit and error_mask fields out of pdata
serial: sh-sci: Support resources passed through platform resources
serial: sh-sci: Don't check IRQ in verify port operation
serial: sh-sci: Set the UPF_FIXED_PORT flag
serial: sh-sci: Remove duplicate interrupt check in verify port op
serial: sh-sci: Simplify baud rate calculation algorithms
serial: sh-sci: Remove baud rate calculation algorithm 5
serial: sh-sci: Sort headers alphabetically
ARM: EXYNOS: Kill exynos_pm_late_initcall()
ARM: EXYNOS: Consolidate selection of PM_GENERIC_DOMAINS for Exynos4
ARM: at91: switch Calao QIL-A9260 board to DT
clk: at91: fix pmc_clk_ids data type attriubte
PM / devfreq: use inclusion <mach/map.h> instead of <plat/map-s5p.h>
ARM: EXYNOS: remove <mach/regs-clock.h> for exynos
...
Diffstat (limited to 'drivers/clk/at91/clk-programmable.c')
-rw-r--r-- | drivers/clk/at91/clk-programmable.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c new file mode 100644 index 000000000000..fd792b203eaf --- /dev/null +++ b/drivers/clk/at91/clk-programmable.c @@ -0,0 +1,366 @@ +/* + * 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" + +#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; + unsigned int irq; + wait_queue_head_t wait; + u8 id; + u8 css; + u8 pres; + u8 slckmck; + const struct clk_programmable_layout *layout; +}; + +#define to_clk_programmable(hw) container_of(hw, struct clk_programmable, hw) + + +static irqreturn_t clk_programmable_irq_handler(int irq, void *dev_id) +{ + struct clk_programmable *prog = (struct clk_programmable *)dev_id; + + wake_up(&prog->wait); + + return IRQ_HANDLED; +} + +static int clk_programmable_prepare(struct clk_hw *hw) +{ + u32 tmp; + struct clk_programmable *prog = to_clk_programmable(hw); + struct at91_pmc *pmc = prog->pmc; + const struct clk_programmable_layout *layout = prog->layout; + u8 id = prog->id; + u32 mask = PROG_STATUS_MASK(id); + + tmp = prog->css | (prog->pres << layout->pres_shift); + if (layout->have_slck_mck && prog->slckmck) + tmp |= AT91_PMC_CSSMCK_MCK; + + pmc_write(pmc, AT91_PMC_PCKR(id), tmp); + + while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) + wait_event(prog->wait, pmc_read(pmc, AT91_PMC_SR) & mask); + + return 0; +} + +static int clk_programmable_is_ready(struct clk_hw *hw) +{ + struct clk_programmable *prog = to_clk_programmable(hw); + struct at91_pmc *pmc = prog->pmc; + + return !!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_PCKR(prog->id)); +} + +static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + u32 tmp; + 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)); + prog->pres = (tmp >> layout->pres_shift) & PROG_PRES_MASK; + + return parent_rate >> prog->pres; +} + +static long clk_programmable_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + unsigned long best_rate = *parent_rate; + unsigned long best_diff; + unsigned long new_diff; + unsigned long cur_rate; + int shift = shift; + + if (rate > *parent_rate) + return *parent_rate; + else + best_diff = *parent_rate - rate; + + if (!best_diff) + return best_rate; + + for (shift = 1; shift < PROG_PRES_MASK; shift++) { + cur_rate = *parent_rate >> shift; + + if (cur_rate > rate) + new_diff = cur_rate - rate; + else + new_diff = rate - cur_rate; + + if (!new_diff) + return cur_rate; + + if (new_diff < best_diff) { + best_diff = new_diff; + best_rate = cur_rate; + } + + if (rate > cur_rate) + break; + } + + return best_rate; +} + +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; + if (index > layout->css_mask) { + if (index > PROG_MAX_RM9200_CSS && layout->have_slck_mck) { + prog->css = 0; + prog->slckmck = 1; + return 0; + } else { + return -EINVAL; + } + } + + prog->css = 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)); + prog->css = tmp & layout->css_mask; + ret = prog->css; + if (layout->have_slck_mck) { + prog->slckmck = !!(tmp & AT91_PMC_CSSMCK_MCK); + if (prog->slckmck && !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); + unsigned long best_rate = parent_rate; + unsigned long best_diff; + unsigned long new_diff; + unsigned long cur_rate; + int shift = 0; + + if (rate > parent_rate) + return parent_rate; + else + best_diff = parent_rate - rate; + + if (!best_diff) { + prog->pres = shift; + return 0; + } + + for (shift = 1; shift < PROG_PRES_MASK; shift++) { + cur_rate = parent_rate >> shift; + + if (cur_rate > rate) + new_diff = cur_rate - rate; + else + new_diff = rate - cur_rate; + + if (!new_diff) + break; + + if (new_diff < best_diff) { + best_diff = new_diff; + best_rate = cur_rate; + } + + if (rate > cur_rate) + break; + } + + prog->pres = shift; + return 0; +} + +static const struct clk_ops programmable_ops = { + .prepare = clk_programmable_prepare, + .is_prepared = clk_programmable_is_ready, + .recalc_rate = clk_programmable_recalc_rate, + .round_rate = clk_programmable_round_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, unsigned int irq, + const char *name, const char **parent_names, + u8 num_parents, u8 id, + const struct clk_programmable_layout *layout) +{ + int ret; + struct clk_programmable *prog; + struct clk *clk = NULL; + struct clk_init_data init; + char irq_name[11]; + + 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; + prog->irq = irq; + init_waitqueue_head(&prog->wait); + irq_set_status_flags(prog->irq, IRQ_NOAUTOEN); + snprintf(irq_name, sizeof(irq_name), "clk-prog%d", id); + ret = request_irq(prog->irq, clk_programmable_irq_handler, + IRQF_TRIGGER_HIGH, irq_name, prog); + if (ret) + return ERR_PTR(ret); + + 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; + int i; + unsigned int irq; + struct clk *clk; + int num_parents; + const char *parent_names[PROG_SOURCE_MAX]; + const char *name; + struct device_node *progclknp; + + num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells"); + if (num_parents <= 0 || num_parents > PROG_SOURCE_MAX) + return; + + for (i = 0; i < num_parents; ++i) { + parent_names[i] = of_clk_get_parent_name(np, i); + if (!parent_names[i]) + return; + } + + 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; + + irq = irq_of_parse_and_map(progclknp, 0); + if (!irq) + continue; + + clk = at91_clk_register_programmable(pmc, irq, 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); +} |