Revision 80ef4464d5e27408685e609d389663aad46644b9 authored by Robert Richter on 20 March 2019, 18:57:23 UTC, committed by Joerg Roedel on 22 March 2019, 11:01:58 UTC
If a 32 bit allocation request is too big to possibly succeed, it
early exits with a failure and then should never update max32_alloc_
size. This patch fixes current code, now the size is only updated if
the slow path failed while walking the tree. Without the fix the
allocation may enter the slow path again even if there was a failure
before of a request with the same or a smaller size.
Cc: <stable@vger.kernel.org> # 4.20+
Fixes: bee60e94a1e2 ("iommu/iova: Optimise attempts to allocate iova from 32bit address range")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Robert Richter <rrichter@marvell.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
1 parent 4e50ce0
pwm-imx27.c
// SPDX-License-Identifier: GPL-2.0
/*
* simple driver for PWM (Pulse Width Modulator) controller
*
* Derived from pxa PWM driver by eric miao <eric.miao@marvell.com>
*/
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>
#define MX3_PWMCR 0x00 /* PWM Control Register */
#define MX3_PWMSR 0x04 /* PWM Status Register */
#define MX3_PWMSAR 0x0C /* PWM Sample Register */
#define MX3_PWMPR 0x10 /* PWM Period Register */
#define MX3_PWMCR_FWM GENMASK(27, 26)
#define MX3_PWMCR_STOPEN BIT(25)
#define MX3_PWMCR_DOZEN BIT(24)
#define MX3_PWMCR_WAITEN BIT(23)
#define MX3_PWMCR_DBGEN BIT(22)
#define MX3_PWMCR_BCTR BIT(21)
#define MX3_PWMCR_HCTR BIT(20)
#define MX3_PWMCR_POUTC GENMASK(19, 18)
#define MX3_PWMCR_POUTC_NORMAL 0
#define MX3_PWMCR_POUTC_INVERTED 1
#define MX3_PWMCR_POUTC_OFF 2
#define MX3_PWMCR_CLKSRC GENMASK(17, 16)
#define MX3_PWMCR_CLKSRC_OFF 0
#define MX3_PWMCR_CLKSRC_IPG 1
#define MX3_PWMCR_CLKSRC_IPG_HIGH 2
#define MX3_PWMCR_CLKSRC_IPG_32K 3
#define MX3_PWMCR_PRESCALER GENMASK(15, 4)
#define MX3_PWMCR_SWR BIT(3)
#define MX3_PWMCR_REPEAT GENMASK(2, 1)
#define MX3_PWMCR_REPEAT_1X 0
#define MX3_PWMCR_REPEAT_2X 1
#define MX3_PWMCR_REPEAT_4X 2
#define MX3_PWMCR_REPEAT_8X 3
#define MX3_PWMCR_EN BIT(0)
#define MX3_PWMSR_FWE BIT(6)
#define MX3_PWMSR_CMP BIT(5)
#define MX3_PWMSR_ROV BIT(4)
#define MX3_PWMSR_FE BIT(3)
#define MX3_PWMSR_FIFOAV GENMASK(2, 0)
#define MX3_PWMSR_FIFOAV_EMPTY 0
#define MX3_PWMSR_FIFOAV_1WORD 1
#define MX3_PWMSR_FIFOAV_2WORDS 2
#define MX3_PWMSR_FIFOAV_3WORDS 3
#define MX3_PWMSR_FIFOAV_4WORDS 4
#define MX3_PWMCR_PRESCALER_SET(x) FIELD_PREP(MX3_PWMCR_PRESCALER, (x) - 1)
#define MX3_PWMCR_PRESCALER_GET(x) (FIELD_GET(MX3_PWMCR_PRESCALER, \
(x)) + 1)
#define MX3_PWM_SWR_LOOP 5
/* PWMPR register value of 0xffff has the same effect as 0xfffe */
#define MX3_PWMPR_MAX 0xfffe
struct pwm_imx27_chip {
struct clk *clk_ipg;
struct clk *clk_per;
void __iomem *mmio_base;
struct pwm_chip chip;
};
#define to_pwm_imx27_chip(chip) container_of(chip, struct pwm_imx27_chip, chip)
static int pwm_imx27_clk_prepare_enable(struct pwm_chip *chip)
{
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
int ret;
ret = clk_prepare_enable(imx->clk_ipg);
if (ret)
return ret;
ret = clk_prepare_enable(imx->clk_per);
if (ret) {
clk_disable_unprepare(imx->clk_ipg);
return ret;
}
return 0;
}
static void pwm_imx27_clk_disable_unprepare(struct pwm_chip *chip)
{
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
clk_disable_unprepare(imx->clk_per);
clk_disable_unprepare(imx->clk_ipg);
}
static void pwm_imx27_get_state(struct pwm_chip *chip,
struct pwm_device *pwm, struct pwm_state *state)
{
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
u32 period, prescaler, pwm_clk, val;
u64 tmp;
int ret;
ret = pwm_imx27_clk_prepare_enable(chip);
if (ret < 0)
return;
val = readl(imx->mmio_base + MX3_PWMCR);
if (val & MX3_PWMCR_EN)
state->enabled = true;
else
state->enabled = false;
switch (FIELD_GET(MX3_PWMCR_POUTC, val)) {
case MX3_PWMCR_POUTC_NORMAL:
state->polarity = PWM_POLARITY_NORMAL;
break;
case MX3_PWMCR_POUTC_INVERTED:
state->polarity = PWM_POLARITY_INVERSED;
break;
default:
dev_warn(chip->dev, "can't set polarity, output disconnected");
}
prescaler = MX3_PWMCR_PRESCALER_GET(val);
pwm_clk = clk_get_rate(imx->clk_per);
pwm_clk = DIV_ROUND_CLOSEST_ULL(pwm_clk, prescaler);
val = readl(imx->mmio_base + MX3_PWMPR);
period = val >= MX3_PWMPR_MAX ? MX3_PWMPR_MAX : val;
/* PWMOUT (Hz) = PWMCLK / (PWMPR + 2) */
tmp = NSEC_PER_SEC * (u64)(period + 2);
state->period = DIV_ROUND_CLOSEST_ULL(tmp, pwm_clk);
/* PWMSAR can be read only if PWM is enabled */
if (state->enabled) {
val = readl(imx->mmio_base + MX3_PWMSAR);
tmp = NSEC_PER_SEC * (u64)(val);
state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, pwm_clk);
} else {
state->duty_cycle = 0;
}
if (!state->enabled)
pwm_imx27_clk_disable_unprepare(chip);
}
static void pwm_imx27_sw_reset(struct pwm_chip *chip)
{
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
struct device *dev = chip->dev;
int wait_count = 0;
u32 cr;
writel(MX3_PWMCR_SWR, imx->mmio_base + MX3_PWMCR);
do {
usleep_range(200, 1000);
cr = readl(imx->mmio_base + MX3_PWMCR);
} while ((cr & MX3_PWMCR_SWR) &&
(wait_count++ < MX3_PWM_SWR_LOOP));
if (cr & MX3_PWMCR_SWR)
dev_warn(dev, "software reset timeout\n");
}
static void pwm_imx27_wait_fifo_slot(struct pwm_chip *chip,
struct pwm_device *pwm)
{
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
struct device *dev = chip->dev;
unsigned int period_ms;
int fifoav;
u32 sr;
sr = readl(imx->mmio_base + MX3_PWMSR);
fifoav = FIELD_GET(MX3_PWMSR_FIFOAV, sr);
if (fifoav == MX3_PWMSR_FIFOAV_4WORDS) {
period_ms = DIV_ROUND_UP(pwm_get_period(pwm),
NSEC_PER_MSEC);
msleep(period_ms);
sr = readl(imx->mmio_base + MX3_PWMSR);
if (fifoav == FIELD_GET(MX3_PWMSR_FIFOAV, sr))
dev_warn(dev, "there is no free FIFO slot\n");
}
}
static int pwm_imx27_apply(struct pwm_chip *chip, struct pwm_device *pwm,
struct pwm_state *state)
{
unsigned long period_cycles, duty_cycles, prescale;
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
struct pwm_state cstate;
unsigned long long c;
int ret;
u32 cr;
pwm_get_state(pwm, &cstate);
if (state->enabled) {
c = clk_get_rate(imx->clk_per);
c *= state->period;
do_div(c, 1000000000);
period_cycles = c;
prescale = period_cycles / 0x10000 + 1;
period_cycles /= prescale;
c = (unsigned long long)period_cycles * state->duty_cycle;
do_div(c, state->period);
duty_cycles = c;
/*
* according to imx pwm RM, the real period value should be
* PERIOD value in PWMPR plus 2.
*/
if (period_cycles > 2)
period_cycles -= 2;
else
period_cycles = 0;
/*
* Wait for a free FIFO slot if the PWM is already enabled, and
* flush the FIFO if the PWM was disabled and is about to be
* enabled.
*/
if (cstate.enabled) {
pwm_imx27_wait_fifo_slot(chip, pwm);
} else {
ret = pwm_imx27_clk_prepare_enable(chip);
if (ret)
return ret;
pwm_imx27_sw_reset(chip);
}
writel(duty_cycles, imx->mmio_base + MX3_PWMSAR);
writel(period_cycles, imx->mmio_base + MX3_PWMPR);
cr = MX3_PWMCR_PRESCALER_SET(prescale) |
MX3_PWMCR_STOPEN | MX3_PWMCR_DOZEN | MX3_PWMCR_WAITEN |
FIELD_PREP(MX3_PWMCR_CLKSRC, MX3_PWMCR_CLKSRC_IPG_HIGH) |
MX3_PWMCR_DBGEN | MX3_PWMCR_EN;
if (state->polarity == PWM_POLARITY_INVERSED)
cr |= FIELD_PREP(MX3_PWMCR_POUTC,
MX3_PWMCR_POUTC_INVERTED);
writel(cr, imx->mmio_base + MX3_PWMCR);
} else if (cstate.enabled) {
writel(0, imx->mmio_base + MX3_PWMCR);
pwm_imx27_clk_disable_unprepare(chip);
}
return 0;
}
static const struct pwm_ops pwm_imx27_ops = {
.apply = pwm_imx27_apply,
.get_state = pwm_imx27_get_state,
.owner = THIS_MODULE,
};
static const struct of_device_id pwm_imx27_dt_ids[] = {
{ .compatible = "fsl,imx27-pwm", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, pwm_imx27_dt_ids);
static int pwm_imx27_probe(struct platform_device *pdev)
{
struct pwm_imx27_chip *imx;
struct resource *r;
imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL);
if (imx == NULL)
return -ENOMEM;
platform_set_drvdata(pdev, imx);
imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(imx->clk_ipg)) {
dev_err(&pdev->dev, "getting ipg clock failed with %ld\n",
PTR_ERR(imx->clk_ipg));
return PTR_ERR(imx->clk_ipg);
}
imx->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(imx->clk_per)) {
int ret = PTR_ERR(imx->clk_per);
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev,
"failed to get peripheral clock: %d\n",
ret);
return ret;
}
imx->chip.ops = &pwm_imx27_ops;
imx->chip.dev = &pdev->dev;
imx->chip.base = -1;
imx->chip.npwm = 1;
imx->chip.of_xlate = of_pwm_xlate_with_flags;
imx->chip.of_pwm_n_cells = 3;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx->mmio_base = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(imx->mmio_base))
return PTR_ERR(imx->mmio_base);
return pwmchip_add(&imx->chip);
}
static int pwm_imx27_remove(struct platform_device *pdev)
{
struct pwm_imx27_chip *imx;
imx = platform_get_drvdata(pdev);
pwm_imx27_clk_disable_unprepare(&imx->chip);
return pwmchip_remove(&imx->chip);
}
static struct platform_driver imx_pwm_driver = {
.driver = {
.name = "pwm-imx27",
.of_match_table = pwm_imx27_dt_ids,
},
.probe = pwm_imx27_probe,
.remove = pwm_imx27_remove,
};
module_platform_driver(imx_pwm_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
Computing file changes ...
