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cpufreq: brcmstb-avs-cpufreq: remove development debug support
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This debug code was helpful while developing the driver, but it isn't
being used for anything anymore.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Markus Mayer authored and Rafael J. Wysocki committed Apr 24, 2018
1 parent 6d08b06 commit ee53a65
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Showing 2 changed files with 1 addition and 332 deletions.
10 changes: 0 additions & 10 deletions drivers/cpufreq/Kconfig.arm
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Original file line number Diff line number Diff line change
Expand Up @@ -71,16 +71,6 @@ config ARM_BRCMSTB_AVS_CPUFREQ

Say Y, if you have a Broadcom SoC with AVS support for DFS or DVFS.

config ARM_BRCMSTB_AVS_CPUFREQ_DEBUG
bool "Broadcom STB AVS CPUfreq driver sysfs debug capability"
depends on ARM_BRCMSTB_AVS_CPUFREQ
help
Enabling this option turns on debug support via sysfs under
/sys/kernel/debug/brcmstb-avs-cpufreq. It is possible to read all and
write some AVS mailbox registers through sysfs entries.

If in doubt, say N.

config ARM_EXYNOS5440_CPUFREQ
tristate "SAMSUNG EXYNOS5440"
depends on SOC_EXYNOS5440
Expand Down
323 changes: 1 addition & 322 deletions drivers/cpufreq/brcmstb-avs-cpufreq.c
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Original file line number Diff line number Diff line change
Expand Up @@ -49,13 +49,6 @@
#include <linux/platform_device.h>
#include <linux/semaphore.h>

#ifdef CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG
#include <linux/ctype.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#endif

/* Max number of arguments AVS calls take */
#define AVS_MAX_CMD_ARGS 4
/*
Expand Down Expand Up @@ -182,88 +175,11 @@ struct private_data {
void __iomem *base;
void __iomem *avs_intr_base;
struct device *dev;
#ifdef CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG
struct dentry *debugfs;
#endif
struct completion done;
struct semaphore sem;
struct pmap pmap;
};

#ifdef CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG

enum debugfs_format {
DEBUGFS_NORMAL,
DEBUGFS_FLOAT,
DEBUGFS_REV,
};

struct debugfs_data {
struct debugfs_entry *entry;
struct private_data *priv;
};

struct debugfs_entry {
char *name;
u32 offset;
fmode_t mode;
enum debugfs_format format;
};

#define DEBUGFS_ENTRY(name, mode, format) { \
#name, AVS_MBOX_##name, mode, format \
}

/*
* These are used for debugfs only. Otherwise we use AVS_MBOX_PARAM() directly.
*/
#define AVS_MBOX_PARAM1 AVS_MBOX_PARAM(0)
#define AVS_MBOX_PARAM2 AVS_MBOX_PARAM(1)
#define AVS_MBOX_PARAM3 AVS_MBOX_PARAM(2)
#define AVS_MBOX_PARAM4 AVS_MBOX_PARAM(3)

/*
* This table stores the name, access permissions and offset for each hardware
* register and is used to generate debugfs entries.
*/
static struct debugfs_entry debugfs_entries[] = {
DEBUGFS_ENTRY(COMMAND, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(STATUS, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(VOLTAGE0, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(TEMP0, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(PV0, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(MV0, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(PARAM1, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(PARAM2, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(PARAM3, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(PARAM4, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(REVISION, 0, DEBUGFS_REV),
DEBUGFS_ENTRY(PSTATE, 0, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(HEARTBEAT, 0, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(MAGIC, S_IWUSR, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(SIGMA_HVT, 0, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(SIGMA_SVT, 0, DEBUGFS_NORMAL),
DEBUGFS_ENTRY(VOLTAGE1, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(TEMP1, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(PV1, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(MV1, 0, DEBUGFS_FLOAT),
DEBUGFS_ENTRY(FREQUENCY, 0, DEBUGFS_NORMAL),
};

static int brcm_avs_target_index(struct cpufreq_policy *, unsigned int);

static char *__strtolower(char *s)
{
char *p;

for (p = s; *p; p++)
*p = tolower(*p);

return s;
}

#endif /* CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG */

static void __iomem *__map_region(const char *name)
{
struct device_node *np;
Expand Down Expand Up @@ -516,238 +432,6 @@ brcm_avs_get_freq_table(struct device *dev, struct private_data *priv)
return table;
}

#ifdef CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG

#define MANT(x) (unsigned int)(abs((x)) / 1000)
#define FRAC(x) (unsigned int)(abs((x)) - abs((x)) / 1000 * 1000)

static int brcm_avs_debug_show(struct seq_file *s, void *data)
{
struct debugfs_data *dbgfs = s->private;
void __iomem *base;
u32 val, offset;

if (!dbgfs) {
seq_puts(s, "No device pointer\n");
return 0;
}

base = dbgfs->priv->base;
offset = dbgfs->entry->offset;
val = readl(base + offset);
switch (dbgfs->entry->format) {
case DEBUGFS_NORMAL:
seq_printf(s, "%u\n", val);
break;
case DEBUGFS_FLOAT:
seq_printf(s, "%d.%03d\n", MANT(val), FRAC(val));
break;
case DEBUGFS_REV:
seq_printf(s, "%c.%c.%c.%c\n", (val >> 24 & 0xff),
(val >> 16 & 0xff), (val >> 8 & 0xff),
val & 0xff);
break;
}
seq_printf(s, "0x%08x\n", val);

return 0;
}

#undef MANT
#undef FRAC

static ssize_t brcm_avs_seq_write(struct file *file, const char __user *buf,
size_t size, loff_t *ppos)
{
struct seq_file *s = file->private_data;
struct debugfs_data *dbgfs = s->private;
struct private_data *priv = dbgfs->priv;
void __iomem *base, *avs_intr_base;
bool use_issue_command = false;
unsigned long val, offset;
char str[128];
int ret;
char *str_ptr = str;

if (size >= sizeof(str))
return -E2BIG;

memset(str, 0, sizeof(str));
ret = copy_from_user(str, buf, size);
if (ret)
return ret;

base = priv->base;
avs_intr_base = priv->avs_intr_base;
offset = dbgfs->entry->offset;
/*
* Special case writing to "command" entry only: if the string starts
* with a 'c', we use the driver's __issue_avs_command() function.
* Otherwise, we perform a raw write. This should allow testing of raw
* access as well as using the higher level function. (Raw access
* doesn't clear the firmware return status after issuing the command.)
*/
if (str_ptr[0] == 'c' && offset == AVS_MBOX_COMMAND) {
use_issue_command = true;
str_ptr++;
}
if (kstrtoul(str_ptr, 0, &val) != 0)
return -EINVAL;

/*
* Setting the P-state is a special case. We need to update the CPU
* frequency we report.
*/
if (val == AVS_CMD_SET_PSTATE) {
struct cpufreq_policy *policy;
unsigned int pstate;

policy = cpufreq_cpu_get(smp_processor_id());
/* Read back the P-state we are about to set */
pstate = readl(base + AVS_MBOX_PARAM(0));
if (use_issue_command) {
ret = brcm_avs_target_index(policy, pstate);
return ret ? ret : size;
}
policy->cur = policy->freq_table[pstate].frequency;
}

if (use_issue_command) {
ret = __issue_avs_command(priv, val, false, NULL);
} else {
/* Locking here is not perfect, but is only for debug. */
ret = down_interruptible(&priv->sem);
if (ret)
return ret;

writel(val, base + offset);
/* We have to wake up the firmware to process a command. */
if (offset == AVS_MBOX_COMMAND)
writel(AVS_CPU_L2_INT_MASK,
avs_intr_base + AVS_CPU_L2_SET0);
up(&priv->sem);
}

return ret ? ret : size;
}

static struct debugfs_entry *__find_debugfs_entry(const char *name)
{
int i;

for (i = 0; i < ARRAY_SIZE(debugfs_entries); i++)
if (strcasecmp(debugfs_entries[i].name, name) == 0)
return &debugfs_entries[i];

return NULL;
}

static int brcm_avs_debug_open(struct inode *inode, struct file *file)
{
struct debugfs_data *data;
fmode_t fmode;
int ret;

/*
* seq_open(), which is called by single_open(), clears "write" access.
* We need write access to some files, so we preserve our access mode
* and restore it.
*/
fmode = file->f_mode;
/*
* Check access permissions even for root. We don't want to be writing
* to read-only registers. Access for regular users has already been
* checked by the VFS layer.
*/
if ((fmode & FMODE_WRITER) && !(inode->i_mode & S_IWUSR))
return -EACCES;

data = kmalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
/*
* We use the same file system operations for all our debug files. To
* produce specific output, we look up the file name upon opening a
* debugfs entry and map it to a memory offset. This offset is then used
* in the generic "show" function to read a specific register.
*/
data->entry = __find_debugfs_entry(file->f_path.dentry->d_iname);
data->priv = inode->i_private;

ret = single_open(file, brcm_avs_debug_show, data);
if (ret)
kfree(data);
file->f_mode = fmode;

return ret;
}

static int brcm_avs_debug_release(struct inode *inode, struct file *file)
{
struct seq_file *seq_priv = file->private_data;
struct debugfs_data *data = seq_priv->private;

kfree(data);
return single_release(inode, file);
}

static const struct file_operations brcm_avs_debug_ops = {
.open = brcm_avs_debug_open,
.read = seq_read,
.write = brcm_avs_seq_write,
.llseek = seq_lseek,
.release = brcm_avs_debug_release,
};

static void brcm_avs_cpufreq_debug_init(struct platform_device *pdev)
{
struct private_data *priv = platform_get_drvdata(pdev);
struct dentry *dir;
int i;

if (!priv)
return;

dir = debugfs_create_dir(BRCM_AVS_CPUFREQ_NAME, NULL);
if (IS_ERR_OR_NULL(dir))
return;
priv->debugfs = dir;

for (i = 0; i < ARRAY_SIZE(debugfs_entries); i++) {
/*
* The DEBUGFS_ENTRY macro generates uppercase strings. We
* convert them to lowercase before creating the debugfs
* entries.
*/
char *entry = __strtolower(debugfs_entries[i].name);
fmode_t mode = debugfs_entries[i].mode;

if (!debugfs_create_file(entry, S_IFREG | S_IRUGO | mode,
dir, priv, &brcm_avs_debug_ops)) {
priv->debugfs = NULL;
debugfs_remove_recursive(dir);
break;
}
}
}

static void brcm_avs_cpufreq_debug_exit(struct platform_device *pdev)
{
struct private_data *priv = platform_get_drvdata(pdev);

if (priv && priv->debugfs) {
debugfs_remove_recursive(priv->debugfs);
priv->debugfs = NULL;
}
}

#else

static void brcm_avs_cpufreq_debug_init(struct platform_device *pdev) {}
static void brcm_avs_cpufreq_debug_exit(struct platform_device *pdev) {}

#endif /* CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG */

/*
* To ensure the right firmware is running we need to
* - check the MAGIC matches what we expect
Expand Down Expand Up @@ -1016,11 +700,8 @@ static int brcm_avs_cpufreq_probe(struct platform_device *pdev)
return ret;

brcm_avs_driver.driver_data = pdev;
ret = cpufreq_register_driver(&brcm_avs_driver);
if (!ret)
brcm_avs_cpufreq_debug_init(pdev);

return ret;
return cpufreq_register_driver(&brcm_avs_driver);
}

static int brcm_avs_cpufreq_remove(struct platform_device *pdev)
Expand All @@ -1032,8 +713,6 @@ static int brcm_avs_cpufreq_remove(struct platform_device *pdev)
if (ret)
return ret;

brcm_avs_cpufreq_debug_exit(pdev);

priv = platform_get_drvdata(pdev);
iounmap(priv->base);
iounmap(priv->avs_intr_base);
Expand Down

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