linux/arch/arm/mach-omap2/prm_common.c
Linus Torvalds c0fa2373f8 The clk tree changes for 3.18 are dominated by clock drivers. Mostly
fixes and enhancements to existing drivers as well as new drivers. This
 tag contains a bit more arch code than I usually take due to some OMAP2+
 changes. Additionally it contains the restart notifier handlers which
 are merged as a dependency into several trees.
 
 The PXA changes are the only messy part. Due to having a stable tree I
 had to revert one patch and follow up with one more fix near the tip of
 this tag. Some dead code is introduced but it will soon become live code
 after 3.18-rc1 is released as the rest of the PXA family is converted
 over to the common clock framework.
 
 Another trend in this tag is that multiple vendors have started to push
 the complexity of changing their CPU frequency into the clock driver,
 whereas this used to be done in CPUfreq drivers.
 
 Changes to the clk core include a generic gpio-clock type and a
 clk_set_phase() function added to the top-level clk.h api. Due to some
 confusion on the fbdev mailing list the kernel boot parameters
 documentation was updated to further explain the clk_ignore_unused
 parameter, which is often required by users of the simplefb driver.
 Finally some fixes to the locking around the clock debugfs stuff was
 done to prevent deadlocks when interacting with other subsystems.
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Merge tag 'clk-for-linus-3.18' of git://git.linaro.org/people/mike.turquette/linux

Pull clock tree updates from Mike Turquette:
 "The clk tree changes for 3.18 are dominated by clock drivers.  Mostly
  fixes and enhancements to existing drivers as well as new drivers.
  This tag contains a bit more arch code than I usually take due to some
  OMAP2+ changes.  Additionally it contains the restart notifier
  handlers which are merged as a dependency into several trees.

  The PXA changes are the only messy part.  Due to having a stable tree
  I had to revert one patch and follow up with one more fix near the tip
  of this tag.  Some dead code is introduced but it will soon become
  live code after 3.18-rc1 is released as the rest of the PXA family is
  converted over to the common clock framework.

  Another trend in this tag is that multiple vendors have started to
  push the complexity of changing their CPU frequency into the clock
  driver, whereas this used to be done in CPUfreq drivers.

  Changes to the clk core include a generic gpio-clock type and a
  clk_set_phase() function added to the top-level clk.h api.  Due to
  some confusion on the fbdev mailing list the kernel boot parameters
  documentation was updated to further explain the clk_ignore_unused
  parameter, which is often required by users of the simplefb driver.

  Finally some fixes to the locking around the clock debugfs stuff was
  done to prevent deadlocks when interacting with other subsystems."

* tag 'clk-for-linus-3.18' of git://git.linaro.org/people/mike.turquette/linux: (99 commits)
  clk: pxa clocks build system fix
  Revert "arm: pxa: Transition pxa27x to clk framework"
  clk: samsung: register restart handlers for s3c2412 and s3c2443
  clk: rockchip: add restart handler
  clk: rockchip: rk3288: i2s_frac adds flag to set parent's rate
  doc/kernel-parameters.txt: clarify clk_ignore_unused
  arm: pxa: Transition pxa27x to clk framework
  dts: add devicetree bindings for pxa27x clocks
  clk: add pxa27x clock drivers
  arm: pxa: add clock pll selection bits
  clk: dts: document pxa clock binding
  clk: add pxa clocks infrastructure
  clk: gpio-gate: Ensure gpiod_ APIs are prototyped
  clk: ti: dra7-atl-clock: Mark the device as pm_runtime_irq_safe
  clk: ti: LLVMLinux: Move __init outside of type definition
  clk: ti: consider the fact that of_clk_get() might return an error
  clk: ti: dra7-atl-clock: fix a memory leak
  clk: ti: change clock init to use generic of_clk_init
  clk: hix5hd2: add I2C clocks
  clk: hix5hd2: add watchdog0 clocks
  ...
2014-10-15 07:05:03 +02:00

538 lines
15 KiB
C

/*
* OMAP2+ common Power & Reset Management (PRM) IP block functions
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Tero Kristo <t-kristo@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*
* For historical purposes, the API used to configure the PRM
* interrupt handler refers to it as the "PRCM interrupt." The
* underlying registers are located in the PRM on OMAP3/4.
*
* XXX This code should eventually be moved to a PRM driver.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk-provider.h>
#include <linux/clk/ti.h>
#include "soc.h"
#include "prm2xxx_3xxx.h"
#include "prm2xxx.h"
#include "prm3xxx.h"
#include "prm44xx.h"
#include "common.h"
#include "clock.h"
/*
* OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
* XXX this is technically not needed, since
* omap_prcm_register_chain_handler() could allocate this based on the
* actual amount of memory needed for the SoC
*/
#define OMAP_PRCM_MAX_NR_PENDING_REG 2
/*
* prcm_irq_chips: an array of all of the "generic IRQ chips" in use
* by the PRCM interrupt handler code. There will be one 'chip' per
* PRM_{IRQSTATUS,IRQENABLE}_MPU register pair. (So OMAP3 will have
* one "chip" and OMAP4 will have two.)
*/
static struct irq_chip_generic **prcm_irq_chips;
/*
* prcm_irq_setup: the PRCM IRQ parameters for the hardware the code
* is currently running on. Defined and passed by initialization code
* that calls omap_prcm_register_chain_handler().
*/
static struct omap_prcm_irq_setup *prcm_irq_setup;
/* prm_base: base virtual address of the PRM IP block */
void __iomem *prm_base;
u16 prm_features;
/*
* prm_ll_data: function pointers to SoC-specific implementations of
* common PRM functions
*/
static struct prm_ll_data null_prm_ll_data;
static struct prm_ll_data *prm_ll_data = &null_prm_ll_data;
/* Private functions */
/*
* Move priority events from events to priority_events array
*/
static void omap_prcm_events_filter_priority(unsigned long *events,
unsigned long *priority_events)
{
int i;
for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
priority_events[i] =
events[i] & prcm_irq_setup->priority_mask[i];
events[i] ^= priority_events[i];
}
}
/*
* PRCM Interrupt Handler
*
* This is a common handler for the OMAP PRCM interrupts. Pending
* interrupts are detected by a call to prcm_pending_events and
* dispatched accordingly. Clearing of the wakeup events should be
* done by the SoC specific individual handlers.
*/
static void omap_prcm_irq_handler(unsigned int irq, struct irq_desc *desc)
{
unsigned long pending[OMAP_PRCM_MAX_NR_PENDING_REG];
unsigned long priority_pending[OMAP_PRCM_MAX_NR_PENDING_REG];
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned int virtirq;
int nr_irq = prcm_irq_setup->nr_regs * 32;
/*
* If we are suspended, mask all interrupts from PRCM level,
* this does not ack them, and they will be pending until we
* re-enable the interrupts, at which point the
* omap_prcm_irq_handler will be executed again. The
* _save_and_clear_irqen() function must ensure that the PRM
* write to disable all IRQs has reached the PRM before
* returning, or spurious PRCM interrupts may occur during
* suspend.
*/
if (prcm_irq_setup->suspended) {
prcm_irq_setup->save_and_clear_irqen(prcm_irq_setup->saved_mask);
prcm_irq_setup->suspend_save_flag = true;
}
/*
* Loop until all pending irqs are handled, since
* generic_handle_irq() can cause new irqs to come
*/
while (!prcm_irq_setup->suspended) {
prcm_irq_setup->read_pending_irqs(pending);
/* No bit set, then all IRQs are handled */
if (find_first_bit(pending, nr_irq) >= nr_irq)
break;
omap_prcm_events_filter_priority(pending, priority_pending);
/*
* Loop on all currently pending irqs so that new irqs
* cannot starve previously pending irqs
*/
/* Serve priority events first */
for_each_set_bit(virtirq, priority_pending, nr_irq)
generic_handle_irq(prcm_irq_setup->base_irq + virtirq);
/* Serve normal events next */
for_each_set_bit(virtirq, pending, nr_irq)
generic_handle_irq(prcm_irq_setup->base_irq + virtirq);
}
if (chip->irq_ack)
chip->irq_ack(&desc->irq_data);
if (chip->irq_eoi)
chip->irq_eoi(&desc->irq_data);
chip->irq_unmask(&desc->irq_data);
prcm_irq_setup->ocp_barrier(); /* avoid spurious IRQs */
}
/* Public functions */
/**
* omap_prcm_event_to_irq - given a PRCM event name, returns the
* corresponding IRQ on which the handler should be registered
* @name: name of the PRCM interrupt bit to look up - see struct omap_prcm_irq
*
* Returns the Linux internal IRQ ID corresponding to @name upon success,
* or -ENOENT upon failure.
*/
int omap_prcm_event_to_irq(const char *name)
{
int i;
if (!prcm_irq_setup || !name)
return -ENOENT;
for (i = 0; i < prcm_irq_setup->nr_irqs; i++)
if (!strcmp(prcm_irq_setup->irqs[i].name, name))
return prcm_irq_setup->base_irq +
prcm_irq_setup->irqs[i].offset;
return -ENOENT;
}
/**
* omap_prcm_irq_cleanup - reverses memory allocated and other steps
* done by omap_prcm_register_chain_handler()
*
* No return value.
*/
void omap_prcm_irq_cleanup(void)
{
int i;
if (!prcm_irq_setup) {
pr_err("PRCM: IRQ handler not initialized; cannot cleanup\n");
return;
}
if (prcm_irq_chips) {
for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
if (prcm_irq_chips[i])
irq_remove_generic_chip(prcm_irq_chips[i],
0xffffffff, 0, 0);
prcm_irq_chips[i] = NULL;
}
kfree(prcm_irq_chips);
prcm_irq_chips = NULL;
}
kfree(prcm_irq_setup->saved_mask);
prcm_irq_setup->saved_mask = NULL;
kfree(prcm_irq_setup->priority_mask);
prcm_irq_setup->priority_mask = NULL;
irq_set_chained_handler(prcm_irq_setup->irq, NULL);
if (prcm_irq_setup->base_irq > 0)
irq_free_descs(prcm_irq_setup->base_irq,
prcm_irq_setup->nr_regs * 32);
prcm_irq_setup->base_irq = 0;
}
void omap_prcm_irq_prepare(void)
{
prcm_irq_setup->suspended = true;
}
void omap_prcm_irq_complete(void)
{
prcm_irq_setup->suspended = false;
/* If we have not saved the masks, do not attempt to restore */
if (!prcm_irq_setup->suspend_save_flag)
return;
prcm_irq_setup->suspend_save_flag = false;
/*
* Re-enable all masked PRCM irq sources, this causes the PRCM
* interrupt to fire immediately if the events were masked
* previously in the chain handler
*/
prcm_irq_setup->restore_irqen(prcm_irq_setup->saved_mask);
}
/**
* omap_prcm_register_chain_handler - initializes the prcm chained interrupt
* handler based on provided parameters
* @irq_setup: hardware data about the underlying PRM/PRCM
*
* Set up the PRCM chained interrupt handler on the PRCM IRQ. Sets up
* one generic IRQ chip per PRM interrupt status/enable register pair.
* Returns 0 upon success, -EINVAL if called twice or if invalid
* arguments are passed, or -ENOMEM on any other error.
*/
int omap_prcm_register_chain_handler(struct omap_prcm_irq_setup *irq_setup)
{
int nr_regs;
u32 mask[OMAP_PRCM_MAX_NR_PENDING_REG];
int offset, i;
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
if (!irq_setup)
return -EINVAL;
nr_regs = irq_setup->nr_regs;
if (prcm_irq_setup) {
pr_err("PRCM: already initialized; won't reinitialize\n");
return -EINVAL;
}
if (nr_regs > OMAP_PRCM_MAX_NR_PENDING_REG) {
pr_err("PRCM: nr_regs too large\n");
return -EINVAL;
}
prcm_irq_setup = irq_setup;
prcm_irq_chips = kzalloc(sizeof(void *) * nr_regs, GFP_KERNEL);
prcm_irq_setup->saved_mask = kzalloc(sizeof(u32) * nr_regs, GFP_KERNEL);
prcm_irq_setup->priority_mask = kzalloc(sizeof(u32) * nr_regs,
GFP_KERNEL);
if (!prcm_irq_chips || !prcm_irq_setup->saved_mask ||
!prcm_irq_setup->priority_mask) {
pr_err("PRCM: kzalloc failed\n");
goto err;
}
memset(mask, 0, sizeof(mask));
for (i = 0; i < irq_setup->nr_irqs; i++) {
offset = irq_setup->irqs[i].offset;
mask[offset >> 5] |= 1 << (offset & 0x1f);
if (irq_setup->irqs[i].priority)
irq_setup->priority_mask[offset >> 5] |=
1 << (offset & 0x1f);
}
irq_set_chained_handler(irq_setup->irq, omap_prcm_irq_handler);
irq_setup->base_irq = irq_alloc_descs(-1, 0, irq_setup->nr_regs * 32,
0);
if (irq_setup->base_irq < 0) {
pr_err("PRCM: failed to allocate irq descs: %d\n",
irq_setup->base_irq);
goto err;
}
for (i = 0; i < irq_setup->nr_regs; i++) {
gc = irq_alloc_generic_chip("PRCM", 1,
irq_setup->base_irq + i * 32, prm_base,
handle_level_irq);
if (!gc) {
pr_err("PRCM: failed to allocate generic chip\n");
goto err;
}
ct = gc->chip_types;
ct->chip.irq_ack = irq_gc_ack_set_bit;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->regs.ack = irq_setup->ack + i * 4;
ct->regs.mask = irq_setup->mask + i * 4;
irq_setup_generic_chip(gc, mask[i], 0, IRQ_NOREQUEST, 0);
prcm_irq_chips[i] = gc;
}
if (of_have_populated_dt()) {
int irq = omap_prcm_event_to_irq("io");
omap_pcs_legacy_init(irq, irq_setup->reconfigure_io_chain);
}
return 0;
err:
omap_prcm_irq_cleanup();
return -ENOMEM;
}
/**
* omap2_set_globals_prm - set the PRM base address (for early use)
* @prm: PRM base virtual address
*
* XXX Will be replaced when the PRM/CM drivers are completed.
*/
void __init omap2_set_globals_prm(void __iomem *prm)
{
prm_base = prm;
}
/**
* prm_read_reset_sources - return the sources of the SoC's last reset
*
* Return a u32 bitmask representing the reset sources that caused the
* SoC to reset. The low-level per-SoC functions called by this
* function remap the SoC-specific reset source bits into an
* OMAP-common set of reset source bits, defined in
* arch/arm/mach-omap2/prm.h. Returns the standardized reset source
* u32 bitmask from the hardware upon success, or returns (1 <<
* OMAP_UNKNOWN_RST_SRC_ID_SHIFT) if no low-level read_reset_sources()
* function was registered.
*/
u32 prm_read_reset_sources(void)
{
u32 ret = 1 << OMAP_UNKNOWN_RST_SRC_ID_SHIFT;
if (prm_ll_data->read_reset_sources)
ret = prm_ll_data->read_reset_sources();
else
WARN_ONCE(1, "prm: %s: no mapping function defined for reset sources\n", __func__);
return ret;
}
/**
* prm_was_any_context_lost_old - was device context lost? (old API)
* @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
* @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
* @idx: CONTEXT register offset
*
* Return 1 if any bits were set in the *_CONTEXT_* register
* identified by (@part, @inst, @idx), which means that some context
* was lost for that module; otherwise, return 0. XXX Deprecated;
* callers need to use a less-SoC-dependent way to identify hardware
* IP blocks.
*/
bool prm_was_any_context_lost_old(u8 part, s16 inst, u16 idx)
{
bool ret = true;
if (prm_ll_data->was_any_context_lost_old)
ret = prm_ll_data->was_any_context_lost_old(part, inst, idx);
else
WARN_ONCE(1, "prm: %s: no mapping function defined\n",
__func__);
return ret;
}
/**
* prm_clear_context_lost_flags_old - clear context loss flags (old API)
* @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
* @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
* @idx: CONTEXT register offset
*
* Clear hardware context loss bits for the module identified by
* (@part, @inst, @idx). No return value. XXX Deprecated; callers
* need to use a less-SoC-dependent way to identify hardware IP
* blocks.
*/
void prm_clear_context_loss_flags_old(u8 part, s16 inst, u16 idx)
{
if (prm_ll_data->clear_context_loss_flags_old)
prm_ll_data->clear_context_loss_flags_old(part, inst, idx);
else
WARN_ONCE(1, "prm: %s: no mapping function defined\n",
__func__);
}
/**
* prm_register - register per-SoC low-level data with the PRM
* @pld: low-level per-SoC OMAP PRM data & function pointers to register
*
* Register per-SoC low-level OMAP PRM data and function pointers with
* the OMAP PRM common interface. The caller must keep the data
* pointed to by @pld valid until it calls prm_unregister() and
* it returns successfully. Returns 0 upon success, -EINVAL if @pld
* is NULL, or -EEXIST if prm_register() has already been called
* without an intervening prm_unregister().
*/
int prm_register(struct prm_ll_data *pld)
{
if (!pld)
return -EINVAL;
if (prm_ll_data != &null_prm_ll_data)
return -EEXIST;
prm_ll_data = pld;
return 0;
}
/**
* prm_unregister - unregister per-SoC low-level data & function pointers
* @pld: low-level per-SoC OMAP PRM data & function pointers to unregister
*
* Unregister per-SoC low-level OMAP PRM data and function pointers
* that were previously registered with prm_register(). The
* caller may not destroy any of the data pointed to by @pld until
* this function returns successfully. Returns 0 upon success, or
* -EINVAL if @pld is NULL or if @pld does not match the struct
* prm_ll_data * previously registered by prm_register().
*/
int prm_unregister(struct prm_ll_data *pld)
{
if (!pld || prm_ll_data != pld)
return -EINVAL;
prm_ll_data = &null_prm_ll_data;
return 0;
}
static const struct of_device_id omap_prcm_dt_match_table[] = {
{ .compatible = "ti,am3-prcm" },
{ .compatible = "ti,am3-scrm" },
{ .compatible = "ti,am4-prcm" },
{ .compatible = "ti,am4-scrm" },
{ .compatible = "ti,omap2-prcm" },
{ .compatible = "ti,omap2-scrm" },
{ .compatible = "ti,omap3-prm" },
{ .compatible = "ti,omap3-cm" },
{ .compatible = "ti,omap3-scrm" },
{ .compatible = "ti,omap4-cm1" },
{ .compatible = "ti,omap4-prm" },
{ .compatible = "ti,omap4-cm2" },
{ .compatible = "ti,omap4-scrm" },
{ .compatible = "ti,omap5-prm" },
{ .compatible = "ti,omap5-cm-core-aon" },
{ .compatible = "ti,omap5-scrm" },
{ .compatible = "ti,omap5-cm-core" },
{ .compatible = "ti,dra7-prm" },
{ .compatible = "ti,dra7-cm-core-aon" },
{ .compatible = "ti,dra7-cm-core" },
{ }
};
static struct clk_hw_omap memmap_dummy_ck = {
.flags = MEMMAP_ADDRESSING,
};
static u32 prm_clk_readl(void __iomem *reg)
{
return omap2_clk_readl(&memmap_dummy_ck, reg);
}
static void prm_clk_writel(u32 val, void __iomem *reg)
{
omap2_clk_writel(val, &memmap_dummy_ck, reg);
}
static struct ti_clk_ll_ops omap_clk_ll_ops = {
.clk_readl = prm_clk_readl,
.clk_writel = prm_clk_writel,
};
int __init of_prcm_init(void)
{
struct device_node *np;
void __iomem *mem;
int memmap_index = 0;
ti_clk_ll_ops = &omap_clk_ll_ops;
for_each_matching_node(np, omap_prcm_dt_match_table) {
mem = of_iomap(np, 0);
clk_memmaps[memmap_index] = mem;
ti_dt_clk_init_provider(np, memmap_index);
memmap_index++;
}
return 0;
}
static int __init prm_late_init(void)
{
if (prm_ll_data->late_init)
return prm_ll_data->late_init();
return 0;
}
subsys_initcall(prm_late_init);