On Thu, Sep 10, 2020 at 03:01:47PM +0200, Alexandre Bailon wrote: > The DSP could be debugged using JTAG. > The support of JTAG could enabled at build time and it could be enabled > using debugfs. > > Signed-off-by: Alexandre Bailon <abailon@xxxxxxxxxxxx> > --- > drivers/remoteproc/Kconfig | 9 +++ > drivers/remoteproc/mtk_apu.c | 151 ++++++++++++++++++++++++++++++++++- > 2 files changed, 159 insertions(+), 1 deletion(-) > > diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig > index 4ebea57bf4c8..310462346bd8 100644 > --- a/drivers/remoteproc/Kconfig > +++ b/drivers/remoteproc/Kconfig > @@ -61,6 +61,15 @@ config MTK_APU > > It's safe to say N here. > > +config MTK_APU_JTAG > + bool "Enable support of JTAG" I think it is better to simply go with "Enable JTAG support" > + depends on MTK_APU > + help > + Say y to enable support of JTAG. Same here. > + By default, JTAG will remain disabled until it is enabled using > + debugfs: remoteproc/remoteproc0/jtag. Write 1 to enable it and s/remoteproc0/remoteprocX > + 0 to disable it. > + > config OMAP_REMOTEPROC > tristate "OMAP remoteproc support" > depends on ARCH_OMAP4 || SOC_OMAP5 || SOC_DRA7XX > diff --git a/drivers/remoteproc/mtk_apu.c b/drivers/remoteproc/mtk_apu.c > index 6d2f577cfde5..07157fdc24ba 100644 > --- a/drivers/remoteproc/mtk_apu.c > +++ b/drivers/remoteproc/mtk_apu.c > @@ -5,6 +5,7 @@ > > #include <linux/bitops.h> > #include <linux/clk.h> > +#include <linux/debugfs.h> > #include <linux/delay.h> > #include <linux/highmem.h> > #include <linux/interrupt.h> > @@ -14,6 +15,7 @@ > #include <linux/kernel.h> > #include <linux/module.h> > #include <linux/of_reserved_mem.h> > +#include <linux/pinctrl/consumer.h> > #include <linux/platform_device.h> > #include <linux/remoteproc.h> > > @@ -48,6 +50,11 @@ > #define CORE_DEFAULT1 (0x00000140) > #define CORE_DEFAULT0_ARUSER_IDMA_USE_IOMMU (0x10 << 0) > #define CORE_DEFAULT0_AWUSER_IDMA_USE_IOMMU (0x10 << 5) > +#define CORE_DEFAULT2 (0x00000144) > +#define CORE_DEFAULT2_DBG_EN BIT(3) > +#define CORE_DEFAULT2_NIDEN BIT(2) > +#define CORE_DEFAULT2_SPNIDEN BIT(1) > +#define CORE_DEFAULT2_SPIDEN BIT(0) > #define CORE_XTENSA_ALTRESETVEC (0x000001F8) > > struct mtk_apu_rproc { > @@ -57,6 +64,13 @@ struct mtk_apu_rproc { > void __iomem *base; > int irq; > struct clk_bulk_data clks[3]; > + > +#ifdef CONFIG_MTK_APU_JTAG > + struct pinctrl *pinctrl; > + struct pinctrl_state *pinctrl_jtag; > + bool jtag_enabled; > + struct mutex jtag_mutex; Move this up to keep all the struct together. > +#endif > }; > > static int mtk_apu_rproc_prepare(struct rproc *rproc) > @@ -166,6 +180,137 @@ static irqreturn_t handle_event(int irq, void *data) > return IRQ_HANDLED; > } > > +#ifdef CONFIG_MTK_APU_JTAG > + > +static int apu_enable_jtag(struct mtk_apu_rproc *apu_rproc) > +{ > + int ret = 0; > + > + mutex_lock(&apu_rproc->jtag_mutex); > + if (apu_rproc->jtag_enabled) { > + ret = -EINVAL; The JTAG is already enabled, I think enabling it again isn't a big deal and should simply return 0 rather than an error. > + goto err_mutex_unlock; > + } > + > + writel(CORE_DEFAULT2_SPNIDEN | CORE_DEFAULT2_SPIDEN | > + CORE_DEFAULT2_NIDEN | CORE_DEFAULT2_DBG_EN, > + apu_rproc->base + CORE_DEFAULT2); > + > + apu_rproc->jtag_enabled = 1; s/1/true > + > +err_mutex_unlock: > + mutex_unlock(&apu_rproc->jtag_mutex); > + > + return ret; > +} > + > +static int apu_disable_jtag(struct mtk_apu_rproc *apu_rproc) > +{ > + int ret = 0; > + > + mutex_lock(&apu_rproc->jtag_mutex); > + if (!apu_rproc->jtag_enabled) { > + ret = -EINVAL; Same as above > + goto err_mutex_unlock; > + } > + > + writel(0, apu_rproc->base + CORE_DEFAULT2); > + > + apu_rproc->jtag_enabled = 0; s/0/false Thanks for the patience, Mathieu > + > +err_mutex_unlock: > + mutex_unlock(&apu_rproc->jtag_mutex); > + > + return ret; > +} > + > +static ssize_t rproc_jtag_read(struct file *filp, char __user *userbuf, > + size_t count, loff_t *ppos) > +{ > + struct rproc *rproc = filp->private_data; > + struct mtk_apu_rproc *apu_rproc = (struct mtk_apu_rproc *)rproc->priv; > + char *buf = apu_rproc->jtag_enabled ? "enabled\n" : "disabled\n"; > + > + return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf)); > +} > + > +static ssize_t rproc_jtag_write(struct file *filp, const char __user *user_buf, > + size_t count, loff_t *ppos) > +{ > + struct rproc *rproc = filp->private_data; > + struct mtk_apu_rproc *apu_rproc = (struct mtk_apu_rproc *)rproc->priv; > + char buf[10]; > + int ret; > + > + if (count < 1 || count > sizeof(buf)) > + return -EINVAL; > + > + ret = copy_from_user(buf, user_buf, count); > + if (ret) > + return -EFAULT; > + > + /* remove end of line */ > + if (buf[count - 1] == '\n') > + buf[count - 1] = '\0'; > + > + if (!strncmp(buf, "enabled", count)) > + ret = apu_enable_jtag(apu_rproc); > + else if (!strncmp(buf, "disabled", count)) > + ret = apu_disable_jtag(apu_rproc); > + else > + return -EINVAL; > + > + return ret ? ret : count; > +} > + > +static const struct file_operations rproc_jtag_ops = { > + .read = rproc_jtag_read, > + .write = rproc_jtag_write, > + .open = simple_open, > +}; > + > +static int apu_jtag_probe(struct mtk_apu_rproc *apu_rproc) > +{ > + int ret; > + > + if (!apu_rproc->rproc->dbg_dir) > + return -ENODEV; > + > + apu_rproc->pinctrl = devm_pinctrl_get(apu_rproc->dev); > + if (IS_ERR(apu_rproc->pinctrl)) { > + dev_warn(apu_rproc->dev, "Failed to find JTAG pinctrl\n"); > + return PTR_ERR(apu_rproc->pinctrl); > + } > + > + apu_rproc->pinctrl_jtag = pinctrl_lookup_state(apu_rproc->pinctrl, > + "jtag"); > + if (IS_ERR(apu_rproc->pinctrl_jtag)) > + return PTR_ERR(apu_rproc->pinctrl_jtag); > + > + ret = pinctrl_select_state(apu_rproc->pinctrl, > + apu_rproc->pinctrl_jtag); > + if (ret < 0) > + return ret; > + > + mutex_init(&apu_rproc->jtag_mutex); > + > + debugfs_create_file("jtag", 0600, apu_rproc->rproc->dbg_dir, > + apu_rproc->rproc, &rproc_jtag_ops); > + > + return 0; > +} > +#else > +static int apu_jtag_probe(struct mtk_apu_rproc *apu_rproc) > +{ > + return 0; > +} > + > +static int apu_disable_jtag(struct mtk_apu_rproc *apu_rproc) > +{ > + return 0; > +} > +#endif /* CONFIG_MTK_APU_JTAG */ > + > static int mtk_apu_rproc_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > @@ -242,6 +387,10 @@ static int mtk_apu_rproc_probe(struct platform_device *pdev) > goto free_mem; > } > > + ret = apu_jtag_probe(apu_rproc); > + if (ret) > + dev_warn(dev, "Failed to configure jtag\n"); > + > return 0; > > free_mem: > @@ -259,7 +408,7 @@ static int mtk_apu_rproc_remove(struct platform_device *pdev) > struct device *dev = &pdev->dev; > > disable_irq(apu_rproc->irq); > - > + apu_disable_jtag(apu_rproc); > rproc_del(rproc); > of_reserved_mem_device_release(dev); > rproc_free(rproc); > -- > 2.26.2 >