From 20ad1de0f14fbd8608bb32de72517f94b42bf60e Mon Sep 17 00:00:00 2001 From: Suman Anna Date: Tue, 8 Dec 2020 15:10:00 +0100 Subject: [PATCH] remoteproc: pru: Add pru-specific debugfs support The remoteproc core creates certain standard debugfs entries, that does not give a whole lot of useful information for the PRUs. The PRU remoteproc driver is enhanced to add additional debugfs entries for PRU. These will be auto-cleaned up when the parent rproc debug directory is removed. The enhanced debugfs support adds two new entries: 'regs' and 'single_step'. The 'regs' dumps out the useful CTRL sub-module registers as well as each of the 32 GPREGs and CT_REGs registers. The GPREGs and CT_REGs though are printed only when the PRU is halted and accessible as per the IP design. The 'single_step' utilizes the single-step execution of the PRU cores. Writing a non-zero value performs a single step, and a zero value restores the PRU to execute in the same mode as the mode before the first single step. (note: if the PRU is halted because of a halt instruction, then no change occurs). Logic for setting the PC and jumping over a halt instruction shall be added in the future. Signed-off-by: Suman Anna Signed-off-by: Grzegorz Jaszczyk Reviewed-by: Mathieu Poirier Link: https://lore.kernel.org/r/20201208141002.17777-5-grzegorz.jaszczyk@linaro.org Signed-off-by: Bjorn Andersson --- drivers/remoteproc/pru_rproc.c | 136 +++++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+) diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c index 72e64d15f0dc..59240fd82f56 100644 --- a/drivers/remoteproc/pru_rproc.c +++ b/drivers/remoteproc/pru_rproc.c @@ -11,6 +11,7 @@ */ #include +#include #include #include #include @@ -25,6 +26,13 @@ /* PRU_ICSS_PRU_CTRL registers */ #define PRU_CTRL_CTRL 0x0000 #define PRU_CTRL_STS 0x0004 +#define PRU_CTRL_WAKEUP_EN 0x0008 +#define PRU_CTRL_CYCLE 0x000C +#define PRU_CTRL_STALL 0x0010 +#define PRU_CTRL_CTBIR0 0x0020 +#define PRU_CTRL_CTBIR1 0x0024 +#define PRU_CTRL_CTPPR0 0x0028 +#define PRU_CTRL_CTPPR1 0x002C /* CTRL register bit-fields */ #define CTRL_CTRL_SOFT_RST_N BIT(0) @@ -34,6 +42,10 @@ #define CTRL_CTRL_SINGLE_STEP BIT(8) #define CTRL_CTRL_RUNSTATE BIT(15) +/* PRU_ICSS_PRU_DEBUG registers */ +#define PRU_DEBUG_GPREG(x) (0x0000 + (x) * 4) +#define PRU_DEBUG_CT_REG(x) (0x0080 + (x) * 4) + /* PRU Core IRAM address masks */ #define PRU_IRAM_ADDR_MASK 0x3ffff #define PRU0_IRAM_ADDR_MASK 0x34000 @@ -73,6 +85,8 @@ enum pru_iomem { * @mapped_irq: virtual interrupt numbers of created fw specific mapping * @pru_interrupt_map: pointer to interrupt mapping description (firmware) * @pru_interrupt_map_sz: pru_interrupt_map size + * @dbg_single_step: debug state variable to set PRU into single step mode + * @dbg_continuous: debug state variable to restore PRU execution mode * @evt_count: number of mapped events */ struct pru_rproc { @@ -85,6 +99,8 @@ struct pru_rproc { unsigned int *mapped_irq; struct pru_irq_rsc *pru_interrupt_map; size_t pru_interrupt_map_sz; + u32 dbg_single_step; + u32 dbg_continuous; u8 evt_count; }; @@ -99,6 +115,124 @@ void pru_control_write_reg(struct pru_rproc *pru, unsigned int reg, u32 val) writel_relaxed(val, pru->mem_regions[PRU_IOMEM_CTRL].va + reg); } +static inline u32 pru_debug_read_reg(struct pru_rproc *pru, unsigned int reg) +{ + return readl_relaxed(pru->mem_regions[PRU_IOMEM_DEBUG].va + reg); +} + +static int regs_show(struct seq_file *s, void *data) +{ + struct rproc *rproc = s->private; + struct pru_rproc *pru = rproc->priv; + int i, nregs = 32; + u32 pru_sts; + int pru_is_running; + + seq_puts(s, "============== Control Registers ==============\n"); + seq_printf(s, "CTRL := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CTRL)); + pru_sts = pru_control_read_reg(pru, PRU_CTRL_STS); + seq_printf(s, "STS (PC) := 0x%08x (0x%08x)\n", pru_sts, pru_sts << 2); + seq_printf(s, "WAKEUP_EN := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_WAKEUP_EN)); + seq_printf(s, "CYCLE := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CYCLE)); + seq_printf(s, "STALL := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_STALL)); + seq_printf(s, "CTBIR0 := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CTBIR0)); + seq_printf(s, "CTBIR1 := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CTBIR1)); + seq_printf(s, "CTPPR0 := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CTPPR0)); + seq_printf(s, "CTPPR1 := 0x%08x\n", + pru_control_read_reg(pru, PRU_CTRL_CTPPR1)); + + seq_puts(s, "=============== Debug Registers ===============\n"); + pru_is_running = pru_control_read_reg(pru, PRU_CTRL_CTRL) & + CTRL_CTRL_RUNSTATE; + if (pru_is_running) { + seq_puts(s, "PRU is executing, cannot print/access debug registers.\n"); + return 0; + } + + for (i = 0; i < nregs; i++) { + seq_printf(s, "GPREG%-2d := 0x%08x\tCT_REG%-2d := 0x%08x\n", + i, pru_debug_read_reg(pru, PRU_DEBUG_GPREG(i)), + i, pru_debug_read_reg(pru, PRU_DEBUG_CT_REG(i))); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(regs); + +/* + * Control PRU single-step mode + * + * This is a debug helper function used for controlling the single-step + * mode of the PRU. The PRU Debug registers are not accessible when the + * PRU is in RUNNING state. + * + * Writing a non-zero value sets the PRU into single-step mode irrespective + * of its previous state. The PRU mode is saved only on the first set into + * a single-step mode. Writing a zero value will restore the PRU into its + * original mode. + */ +static int pru_rproc_debug_ss_set(void *data, u64 val) +{ + struct rproc *rproc = data; + struct pru_rproc *pru = rproc->priv; + u32 reg_val; + + val = val ? 1 : 0; + if (!val && !pru->dbg_single_step) + return 0; + + reg_val = pru_control_read_reg(pru, PRU_CTRL_CTRL); + + if (val && !pru->dbg_single_step) + pru->dbg_continuous = reg_val; + + if (val) + reg_val |= CTRL_CTRL_SINGLE_STEP | CTRL_CTRL_EN; + else + reg_val = pru->dbg_continuous; + + pru->dbg_single_step = val; + pru_control_write_reg(pru, PRU_CTRL_CTRL, reg_val); + + return 0; +} + +static int pru_rproc_debug_ss_get(void *data, u64 *val) +{ + struct rproc *rproc = data; + struct pru_rproc *pru = rproc->priv; + + *val = pru->dbg_single_step; + + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(pru_rproc_debug_ss_fops, pru_rproc_debug_ss_get, + pru_rproc_debug_ss_set, "%llu\n"); + +/* + * Create PRU-specific debugfs entries + * + * The entries are created only if the parent remoteproc debugfs directory + * exists, and will be cleaned up by the remoteproc core. + */ +static void pru_rproc_create_debug_entries(struct rproc *rproc) +{ + if (!rproc->dbg_dir) + return; + + debugfs_create_file("regs", 0400, rproc->dbg_dir, + rproc, ®s_fops); + debugfs_create_file("single_step", 0600, rproc->dbg_dir, + rproc, &pru_rproc_debug_ss_fops); +} + static void pru_dispose_irq_mapping(struct pru_rproc *pru) { while (pru->evt_count--) { @@ -572,6 +706,8 @@ static int pru_rproc_probe(struct platform_device *pdev) return ret; } + pru_rproc_create_debug_entries(rproc); + dev_dbg(dev, "PRU rproc node %pOF probed successfully\n", np); return 0;