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 <s-anna@ti.com>
Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20201208141002.17777-5-grzegorz.jaszczyk@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
This commit is contained in:
Suman Anna 2020-12-08 15:10:00 +01:00 committed by Bjorn Andersson
parent c75c9fdac6
commit 20ad1de0f1

View file

@ -11,6 +11,7 @@
*/
#include <linux/bitops.h>
#include <linux/debugfs.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of_device.h>
@ -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, &regs_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;