| Message ID | 1476310376-32699-4-git-send-email-mmayer@broadcom.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 12 October 2016 at 15:12, Markus Mayer <mmayer@broadcom.com> wrote: > From: Markus Mayer <code@mmayer.net> Ugh. Missed that. In case this version gets applied, would you mind fixing the author address while applying (so they all say Broadcom)? > In order to aid debugging, we add a debugfs interface to the driver > that allows direct interaction with the AVS co-processor. > > The debugfs interface provides a means for reading all and writing some > of the mailbox registers directly from the shell prompt and enables a > user to execute the communications protocol between ARM CPU and AVS CPU > step-by-step. > > This interface should be used for debugging purposes only. > > Signed-off-by: Markus Mayer <mmayer@broadcom.com> > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > drivers/cpufreq/Kconfig.arm | 10 ++ > drivers/cpufreq/brcmstb-avs-cpufreq.c | 323 +++++++++++++++++++++++++++++++++- > 2 files changed, 332 insertions(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm > index d4e3795..43f261e 100644 > --- a/drivers/cpufreq/Kconfig.arm > +++ b/drivers/cpufreq/Kconfig.arm > @@ -23,6 +23,16 @@ 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_DT_BL_CPUFREQ > tristate "Generic probing via DT for ARM big LITTLE CPUfreq driver" > depends on ARM_BIG_LITTLE_CPUFREQ && OF > diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c > index 4415fa0..b761d54 100644 > --- a/drivers/cpufreq/brcmstb-avs-cpufreq.c > +++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c > @@ -49,6 +49,13 @@ > #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 > /* > @@ -175,11 +182,88 @@ 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; > @@ -432,6 +516,238 @@ 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 > @@ -694,8 +1010,11 @@ 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 cpufreq_register_driver(&brcm_avs_driver); > + return ret; > } > > static int brcm_avs_cpufreq_remove(struct platform_device *pdev) > @@ -707,6 +1026,8 @@ 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); > -- > 2.7.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index d4e3795..43f261e 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -23,6 +23,16 @@ 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_DT_BL_CPUFREQ tristate "Generic probing via DT for ARM big LITTLE CPUfreq driver" depends on ARM_BIG_LITTLE_CPUFREQ && OF diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c index 4415fa0..b761d54 100644 --- a/drivers/cpufreq/brcmstb-avs-cpufreq.c +++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c @@ -49,6 +49,13 @@ #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 /* @@ -175,11 +182,88 @@ 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; @@ -432,6 +516,238 @@ 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 @@ -694,8 +1010,11 @@ 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 cpufreq_register_driver(&brcm_avs_driver); + return ret; } static int brcm_avs_cpufreq_remove(struct platform_device *pdev) @@ -707,6 +1026,8 @@ 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);