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dmaengine/ste_dma40: support pm in dma40 

This patch adds power management support to the dma40
driver. The DMA registers are backed up and restored,
during suspend/resume. Also flags to track the dma usage
have been introduced to facilitate this. Patch also includes
few other minor changes, related to formatting, comments.

Signed-off-by: Narayanan G <narayanan.gopalakrishnan@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
hifive-unleashed-5.1
Narayanan G 2011-11-17 17:26:41 +05:30 committed by Vinod Koul
parent ca21a146a4
commit 7fb3e75e18
2 changed files with 259 additions and 19 deletions
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267
drivers/dma/ste_dma40.c
View File

@ -14,6 +14,8 @@
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/err.h>
#include <linux/amba/bus.h>
@ -32,6 +34,9 @@
/* Maximum iterations taken before giving up suspending a channel */
#define D40_SUSPEND_MAX_IT 500
/* Milliseconds */
#define DMA40_AUTOSUSPEND_DELAY 100
/* Hardware requirement on LCLA alignment */
#define LCLA_ALIGNMENT 0x40000
@ -62,6 +67,55 @@ enum d40_command {
D40_DMA_SUSPENDED = 3
};
/*
* These are the registers that has to be saved and later restored
* when the DMA hw is powered off.
* TODO: Add save/restore of D40_DREG_GCC on dma40 v3 or later, if that works.
*/
static u32 d40_backup_regs[] = {
D40_DREG_LCPA,
D40_DREG_LCLA,
D40_DREG_PRMSE,
D40_DREG_PRMSO,
D40_DREG_PRMOE,
D40_DREG_PRMOO,
};
#define BACKUP_REGS_SZ ARRAY_SIZE(d40_backup_regs)
/* TODO: Check if all these registers have to be saved/restored on dma40 v3 */
static u32 d40_backup_regs_v3[] = {
D40_DREG_PSEG1,
D40_DREG_PSEG2,
D40_DREG_PSEG3,
D40_DREG_PSEG4,
D40_DREG_PCEG1,
D40_DREG_PCEG2,
D40_DREG_PCEG3,
D40_DREG_PCEG4,
D40_DREG_RSEG1,
D40_DREG_RSEG2,
D40_DREG_RSEG3,
D40_DREG_RSEG4,
D40_DREG_RCEG1,
D40_DREG_RCEG2,
D40_DREG_RCEG3,
D40_DREG_RCEG4,
};
#define BACKUP_REGS_SZ_V3 ARRAY_SIZE(d40_backup_regs_v3)
static u32 d40_backup_regs_chan[] = {
D40_CHAN_REG_SSCFG,
D40_CHAN_REG_SSELT,
D40_CHAN_REG_SSPTR,
D40_CHAN_REG_SSLNK,
D40_CHAN_REG_SDCFG,
D40_CHAN_REG_SDELT,
D40_CHAN_REG_SDPTR,
D40_CHAN_REG_SDLNK,
};
/**
* struct d40_lli_pool - Structure for keeping LLIs in memory
*
@ -96,7 +150,7 @@ struct d40_lli_pool {
* during a transfer.
* @node: List entry.
* @is_in_client_list: true if the client owns this descriptor.
* the previous one.
* @cyclic: true if this is a cyclic job
*
* This descriptor is used for both logical and physical transfers.
*/
@ -143,6 +197,7 @@ struct d40_lcla_pool {
* channels.
*
* @lock: A lock protection this entity.
* @reserved: True if used by secure world or otherwise.
* @num: The physical channel number of this entity.
* @allocated_src: Bit mapped to show which src event line's are mapped to
* this physical channel. Can also be free or physically allocated.
@ -152,6 +207,7 @@ struct d40_lcla_pool {
*/
struct d40_phy_res {
spinlock_t lock;
bool reserved;
int num;
u32 allocated_src;
u32 allocated_dst;
@ -185,7 +241,6 @@ struct d40_base;
* @src_def_cfg: Default cfg register setting for src.
* @dst_def_cfg: Default cfg register setting for dst.
* @log_def: Default logical channel settings.
* @lcla: Space for one dst src pair for logical channel transfers.
* @lcpa: Pointer to dst and src lcpa settings.
* @runtime_addr: runtime configured address.
* @runtime_direction: runtime configured direction.
@ -241,6 +296,7 @@ struct d40_chan {
* @dma_both: dma_device channels that can do both memcpy and slave transfers.
* @dma_slave: dma_device channels that can do only do slave transfers.
* @dma_memcpy: dma_device channels that can do only do memcpy transfers.
* @phy_chans: Room for all possible physical channels in system.
* @log_chans: Room for all possible logical channels in system.
* @lookup_log_chans: Used to map interrupt number to logical channel. Points
* to log_chans entries.
@ -254,6 +310,13 @@ struct d40_chan {
* @phy_lcpa: The physical address of the LCPA.
* @lcpa_size: The size of the LCPA area.
* @desc_slab: cache for descriptors.
* @reg_val_backup: Here the values of some hardware registers are stored
* before the DMA is powered off. They are restored when the power is back on.
* @reg_val_backup_v3: Backup of registers that only exits on dma40 v3 and
* later.
* @reg_val_backup_chan: Backup data for standard channel parameter registers.
* @gcc_pwr_off_mask: Mask to maintain the channels that can be turned off.
* @initialized: true if the dma has been initialized
*/
struct d40_base {
spinlock_t interrupt_lock;
@ -282,6 +345,11 @@ struct d40_base {
dma_addr_t phy_lcpa;
resource_size_t lcpa_size;
struct kmem_cache *desc_slab;
u32 reg_val_backup[BACKUP_REGS_SZ];
u32 reg_val_backup_v3[BACKUP_REGS_SZ_V3];
u32 *reg_val_backup_chan;
u16 gcc_pwr_off_mask;
bool initialized;
};
/**
@ -479,13 +547,14 @@ static struct d40_desc *d40_desc_get(struct d40_chan *d40c)
struct d40_desc *d;
struct d40_desc *_d;
list_for_each_entry_safe(d, _d, &d40c->client, node)
list_for_each_entry_safe(d, _d, &d40c->client, node) {
if (async_tx_test_ack(&d->txd)) {
d40_desc_remove(d);
desc = d;
memset(desc, 0, sizeof(*desc));
break;
}
}
}
if (!desc)
@ -740,7 +809,61 @@ static int d40_sg_2_dmalen(struct scatterlist *sgl, int sg_len,
return len;
}
/* Support functions for logical channels */
#ifdef CONFIG_PM
static void dma40_backup(void __iomem *baseaddr, u32 *backup,
u32 *regaddr, int num, bool save)
{
int i;
for (i = 0; i < num; i++) {
void __iomem *addr = baseaddr + regaddr[i];
if (save)
backup[i] = readl_relaxed(addr);
else
writel_relaxed(backup[i], addr);
}
}
static void d40_save_restore_registers(struct d40_base *base, bool save)
{
int i;
/* Save/Restore channel specific registers */
for (i = 0; i < base->num_phy_chans; i++) {
void __iomem *addr;
int idx;
if (base->phy_res[i].reserved)
continue;
addr = base->virtbase + D40_DREG_PCBASE + i * D40_DREG_PCDELTA;
idx = i * ARRAY_SIZE(d40_backup_regs_chan);
dma40_backup(addr, &base->reg_val_backup_chan[idx],
d40_backup_regs_chan,
ARRAY_SIZE(d40_backup_regs_chan),
save);
}
/* Save/Restore global registers */
dma40_backup(base->virtbase, base->reg_val_backup,
d40_backup_regs, ARRAY_SIZE(d40_backup_regs),
save);
/* Save/Restore registers only existing on dma40 v3 and later */
if (base->rev >= 3)
dma40_backup(base->virtbase, base->reg_val_backup_v3,
d40_backup_regs_v3,
ARRAY_SIZE(d40_backup_regs_v3),
save);
}
#else
static void d40_save_restore_registers(struct d40_base *base, bool save)
{
}
#endif
static int d40_channel_execute_command(struct d40_chan *d40c,
enum d40_command command)
@ -1013,6 +1136,7 @@ static int d40_pause(struct d40_chan *d40c)
if (!d40c->busy)
return 0;
pm_runtime_get_sync(d40c->base->dev);
spin_lock_irqsave(&d40c->lock, flags);
res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
@ -1025,7 +1149,8 @@ static int d40_pause(struct d40_chan *d40c)
D40_DMA_RUN);
}
}
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
spin_unlock_irqrestore(&d40c->lock, flags);
return res;
}
@ -1039,7 +1164,7 @@ static int d40_resume(struct d40_chan *d40c)
return 0;
spin_lock_irqsave(&d40c->lock, flags);
pm_runtime_get_sync(d40c->base->dev);
if (d40c->base->rev == 0)
if (chan_is_logical(d40c)) {
res = d40_channel_execute_command(d40c,
@ -1057,6 +1182,8 @@ static int d40_resume(struct d40_chan *d40c)
}
no_suspend:
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
spin_unlock_irqrestore(&d40c->lock, flags);
return res;
}
@ -1129,7 +1256,10 @@ static struct d40_desc *d40_queue_start(struct d40_chan *d40c)
d40d = d40_first_queued(d40c);
if (d40d != NULL) {
d40c->busy = true;
if (!d40c->busy)
d40c->busy = true;
pm_runtime_get_sync(d40c->base->dev);
/* Remove from queue */
d40_desc_remove(d40d);
@ -1190,6 +1320,8 @@ static void dma_tc_handle(struct d40_chan *d40c)
if (d40_queue_start(d40c) == NULL)
d40c->busy = false;
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
}
d40c->pending_tx++;
@ -1643,10 +1775,11 @@ static int d40_free_dma(struct d40_chan *d40c)
return -EINVAL;
}
pm_runtime_get_sync(d40c->base->dev);
res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
if (res) {
chan_err(d40c, "suspend failed\n");
return res;
goto out;
}
if (chan_is_logical(d40c)) {
@ -1664,13 +1797,11 @@ static int d40_free_dma(struct d40_chan *d40c)
if (d40_chan_has_events(d40c)) {
res = d40_channel_execute_command(d40c,
D40_DMA_RUN);
if (res) {
if (res)
chan_err(d40c,
"Executing RUN command\n");
return res;
}
}
return 0;
goto out;
}
} else {
(void) d40_alloc_mask_free(phy, is_src, 0);
@ -1680,13 +1811,23 @@ static int d40_free_dma(struct d40_chan *d40c)
res = d40_channel_execute_command(d40c, D40_DMA_STOP);
if (res) {
chan_err(d40c, "Failed to stop channel\n");
return res;
goto out;
}
if (d40c->busy) {
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
}
d40c->busy = false;
d40c->phy_chan = NULL;
d40c->configured = false;
d40c->base->lookup_phy_chans[phy->num] = NULL;
out:
return 0;
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
return res;
}
static bool d40_is_paused(struct d40_chan *d40c)
@ -2016,9 +2157,11 @@ static int d40_alloc_chan_resources(struct dma_chan *chan)
err = d40_allocate_channel(d40c);
if (err) {
chan_err(d40c, "Failed to allocate channel\n");
d40c->configured = false;
goto fail;
}
pm_runtime_get_sync(d40c->base->dev);
/* Fill in basic CFG register values */
d40_phy_cfg(&d40c->dma_cfg, &d40c->src_def_cfg,
&d40c->dst_def_cfg, chan_is_logical(d40c));
@ -2046,6 +2189,8 @@ static int d40_alloc_chan_resources(struct dma_chan *chan)
if (is_free_phy)
d40_config_write(d40c);
fail:
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
spin_unlock_irqrestore(&d40c->lock, flags);
return err;
}
@ -2519,6 +2664,55 @@ failure1:
return err;
}
/* Suspend resume functionality */
#ifdef CONFIG_PM
static int dma40_pm_suspend(struct device *dev)
{
if (!pm_runtime_suspended(dev))
return -EBUSY;
return 0;
}
static int dma40_runtime_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct d40_base *base = platform_get_drvdata(pdev);
d40_save_restore_registers(base, true);
/* Don't disable/enable clocks for v1 due to HW bugs */
if (base->rev != 1)
writel_relaxed(base->gcc_pwr_off_mask,
base->virtbase + D40_DREG_GCC);
return 0;
}
static int dma40_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct d40_base *base = platform_get_drvdata(pdev);
if (base->initialized)
d40_save_restore_registers(base, false);
writel_relaxed(D40_DREG_GCC_ENABLE_ALL,
base->virtbase + D40_DREG_GCC);
return 0;
}
static const struct dev_pm_ops dma40_pm_ops = {
.suspend = dma40_pm_suspend,
.runtime_suspend = dma40_runtime_suspend,
.runtime_resume = dma40_runtime_resume,
};
#define DMA40_PM_OPS (&dma40_pm_ops)
#else
#define DMA40_PM_OPS NULL
#endif
/* Initialization functions. */
static int __init d40_phy_res_init(struct d40_base *base)
@ -2527,6 +2721,7 @@ static int __init d40_phy_res_init(struct d40_base *base)
int num_phy_chans_avail = 0;
u32 val[2];
int odd_even_bit = -2;
int gcc = D40_DREG_GCC_ENA;
val[0] = readl(base->virtbase + D40_DREG_PRSME);
val[1] = readl(base->virtbase + D40_DREG_PRSMO);
@ -2538,9 +2733,17 @@ static int __init d40_phy_res_init(struct d40_base *base)
/* Mark security only channels as occupied */
base->phy_res[i].allocated_src = D40_ALLOC_PHY;
base->phy_res[i].allocated_dst = D40_ALLOC_PHY;
base->phy_res[i].reserved = true;
gcc |= D40_DREG_GCC_EVTGRP_ENA(D40_PHYS_TO_GROUP(i),
D40_DREG_GCC_SRC);
gcc |= D40_DREG_GCC_EVTGRP_ENA(D40_PHYS_TO_GROUP(i),
D40_DREG_GCC_DST);
} else {
base->phy_res[i].allocated_src = D40_ALLOC_FREE;
base->phy_res[i].allocated_dst = D40_ALLOC_FREE;
base->phy_res[i].reserved = false;
num_phy_chans_avail++;
}
spin_lock_init(&base->phy_res[i].lock);
@ -2552,6 +2755,11 @@ static int __init d40_phy_res_init(struct d40_base *base)
base->phy_res[chan].allocated_src = D40_ALLOC_PHY;
base->phy_res[chan].allocated_dst = D40_ALLOC_PHY;
base->phy_res[chan].reserved = true;
gcc |= D40_DREG_GCC_EVTGRP_ENA(D40_PHYS_TO_GROUP(chan),
D40_DREG_GCC_SRC);
gcc |= D40_DREG_GCC_EVTGRP_ENA(D40_PHYS_TO_GROUP(chan),
D40_DREG_GCC_DST);
num_phy_chans_avail--;
}
@ -2572,6 +2780,15 @@ static int __init d40_phy_res_init(struct d40_base *base)
val[0] = val[0] >> 2;
}
/*
* To keep things simple, Enable all clocks initially.
* The clocks will get managed later post channel allocation.
* The clocks for the event lines on which reserved channels exists
* are not managed here.
*/
writel(D40_DREG_GCC_ENABLE_ALL, base->virtbase + D40_DREG_GCC);
base->gcc_pwr_off_mask = gcc;
return num_phy_chans_avail;
}
@ -2699,10 +2916,15 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
goto failure;
}
base->lcla_pool.alloc_map = kzalloc(num_phy_chans *
sizeof(struct d40_desc *) *
D40_LCLA_LINK_PER_EVENT_GRP,
base->reg_val_backup_chan = kmalloc(base->num_phy_chans *
sizeof(d40_backup_regs_chan),
GFP_KERNEL);
if (!base->reg_val_backup_chan)
goto failure;
base->lcla_pool.alloc_map =
kzalloc(num_phy_chans * sizeof(struct d40_desc *)
* D40_LCLA_LINK_PER_EVENT_GRP, GFP_KERNEL);
if (!base->lcla_pool.alloc_map)
goto failure;
@ -2741,9 +2963,9 @@ failure:
static void __init d40_hw_init(struct d40_base *base)
{
static const struct d40_reg_val dma_init_reg[] = {
static struct d40_reg_val dma_init_reg[] = {
/* Clock every part of the DMA block from start */
{ .reg = D40_DREG_GCC, .val = 0x0000ff01},
{ .reg = D40_DREG_GCC, .val = D40_DREG_GCC_ENABLE_ALL},
/* Interrupts on all logical channels */
{ .reg = D40_DREG_LCMIS0, .val = 0xFFFFFFFF},
@ -2960,6 +3182,12 @@ static int __init d40_probe(struct platform_device *pdev)
goto failure;
}
pm_runtime_irq_safe(base->dev);
pm_runtime_set_autosuspend_delay(base->dev, DMA40_AUTOSUSPEND_DELAY);
pm_runtime_use_autosuspend(base->dev);
pm_runtime_enable(base->dev);
pm_runtime_resume(base->dev);
base->initialized = true;
err = d40_dmaengine_init(base, num_reserved_chans);
if (err)
goto failure;
@ -3013,6 +3241,7 @@ static struct platform_driver d40_driver = {
.driver = {
.owner = THIS_MODULE,
.name = D40_NAME,
.pm = DMA40_PM_OPS,
},
};

11
drivers/dma/ste_dma40_ll.h
View File

@ -16,6 +16,8 @@
#define D40_TYPE_TO_GROUP(type) (type / 16)
#define D40_TYPE_TO_EVENT(type) (type % 16)
#define D40_GROUP_SIZE 8
#define D40_PHYS_TO_GROUP(phys) ((phys & (D40_GROUP_SIZE - 1)) / 2)
/* Most bits of the CFG register are the same in log as in phy mode */
#define D40_SREG_CFG_MST_POS 15
@ -123,6 +125,15 @@
/* DMA Register Offsets */
#define D40_DREG_GCC 0x000
#define D40_DREG_GCC_ENA 0x1
/* This assumes that there are only 4 event groups */
#define D40_DREG_GCC_ENABLE_ALL 0xff01
#define D40_DREG_GCC_EVTGRP_POS 8
#define D40_DREG_GCC_SRC 0
#define D40_DREG_GCC_DST 1
#define D40_DREG_GCC_EVTGRP_ENA(x, y) \
(1 << (D40_DREG_GCC_EVTGRP_POS + 2 * x + y))
#define D40_DREG_PRTYP 0x004
#define D40_DREG_PRSME 0x008
#define D40_DREG_PRSMO 0x00C