[PATCH v3 07/15] pinctrl: renesas: pinctrl-rzg2l: Add function pointer for locking/unlocking the PFC register

From: Prabhakar
Date: Thu May 30 2024 - 13:43:32 EST


From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

On the RZ/G2L SoC, the PFCWE bit controls writing to PFC registers.
However, on the RZ/V2H(P) SoC, the PFCWE (REGWE_A on RZ/V2H) bit controls
writing to both PFC and PMC registers. Additionally, BIT(7) B0WI is
undocumented for the PWPR register on RZ/V2H(P) SoC. To accommodate these
differences across SoC variants, introduce the pwpr_pfc_lock_unlock()
function pointer.

Note, in rzg2l_pinctrl_set_pfc_mode() the pwpr_pfc_lock_unlock(.., false)
is now called before PMC read/write and pwpr_pfc_lock_unlock(.., true) is
now called after PMC read/write this is to keep changes minimal for
RZ/V2H(P) SoC.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
---
v2->v3
- Introduced single function pointer to (un)lock
- Updated commit message

RFC->v2
- Introduced function pointer for (un)lock
---
drivers/pinctrl/renesas/pinctrl-rzg2l.c | 44 +++++++++++++++----------
1 file changed, 27 insertions(+), 17 deletions(-)

diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
index 6e3b1adb95f6..a3fd14b95c5a 100644
--- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
+++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
@@ -241,6 +241,8 @@ struct rzg2l_dedicated_configs {
u64 config;
};

+struct rzg2l_pinctrl;
+
struct rzg2l_pinctrl_data {
const char * const *port_pins;
const u64 *port_pin_configs;
@@ -251,6 +253,7 @@ struct rzg2l_pinctrl_data {
const struct rzg2l_hwcfg *hwcfg;
const u64 *variable_pin_cfg;
unsigned int n_variable_pin_cfg;
+ void (*pwpr_pfc_lock_unlock)(struct rzg2l_pinctrl *pctrl, bool lock);
};

/**
@@ -383,7 +386,6 @@ static const u64 r9a07g043f_variable_pin_cfg[] = {
static void rzg2l_pinctrl_set_pfc_mode(struct rzg2l_pinctrl *pctrl,
u8 pin, u8 off, u8 func)
{
- const struct rzg2l_register_offsets *regs = &pctrl->data->hwcfg->regs;
unsigned long flags;
u32 reg;

@@ -394,27 +396,23 @@ static void rzg2l_pinctrl_set_pfc_mode(struct rzg2l_pinctrl *pctrl,
reg &= ~(PM_MASK << (pin * 2));
writew(reg, pctrl->base + PM(off));

+ pctrl->data->pwpr_pfc_lock_unlock(pctrl, false);
+
/* Temporarily switch to GPIO mode with PMC register */
reg = readb(pctrl->base + PMC(off));
writeb(reg & ~BIT(pin), pctrl->base + PMC(off));

- /* Set the PWPR register to allow PFC register to write */
- writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
- writel(PWPR_PFCWE, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=1 */
-
/* Select Pin function mode with PFC register */
reg = readl(pctrl->base + PFC(off));
reg &= ~(PFC_MASK << (pin * 4));
writel(reg | (func << (pin * 4)), pctrl->base + PFC(off));

- /* Set the PWPR register to be write-protected */
- writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
- writel(PWPR_BOWI, pctrl->base + regs->pwpr); /* BOWI=1, PFCWE=0 */
-
/* Switch to Peripheral pin function with PMC register */
reg = readb(pctrl->base + PMC(off));
writeb(reg | BIT(pin), pctrl->base + PMC(off));

+ pctrl->data->pwpr_pfc_lock_unlock(pctrl, true);
+
spin_unlock_irqrestore(&pctrl->lock, flags);
};

@@ -2439,12 +2437,8 @@ static void rzg2l_pinctrl_pm_setup_dedicated_regs(struct rzg2l_pinctrl *pctrl, b
static void rzg2l_pinctrl_pm_setup_pfc(struct rzg2l_pinctrl *pctrl)
{
u32 nports = pctrl->data->n_port_pins / RZG2L_PINS_PER_PORT;
- const struct rzg2l_hwcfg *hwcfg = pctrl->data->hwcfg;
- const struct rzg2l_register_offsets *regs = &hwcfg->regs;

- /* Set the PWPR register to allow PFC register to write. */
- writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
- writel(PWPR_PFCWE, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=1 */
+ pctrl->data->pwpr_pfc_lock_unlock(pctrl, false);

/* Restore port registers. */
for (u32 port = 0; port < nports; port++) {
@@ -2487,9 +2481,7 @@ static void rzg2l_pinctrl_pm_setup_pfc(struct rzg2l_pinctrl *pctrl)
}
}

- /* Set the PWPR register to be write-protected. */
- writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
- writel(PWPR_BOWI, pctrl->base + regs->pwpr); /* BOWI=1, PFCWE=0 */
+ pctrl->data->pwpr_pfc_lock_unlock(pctrl, true);
}

static int rzg2l_pinctrl_suspend_noirq(struct device *dev)
@@ -2551,6 +2543,21 @@ static int rzg2l_pinctrl_resume_noirq(struct device *dev)
return 0;
}

+static void rzg2l_pwpr_pfc_lock_unlock(struct rzg2l_pinctrl *pctrl, bool lock)
+{
+ const struct rzg2l_register_offsets *regs = &pctrl->data->hwcfg->regs;
+
+ if (lock) {
+ /* Set the PWPR register to be write-protected */
+ writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
+ writel(PWPR_BOWI, pctrl->base + regs->pwpr); /* BOWI=1, PFCWE=0 */
+ } else {
+ /* Set the PWPR register to allow PFC register to write */
+ writel(0x0, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=0 */
+ writel(PWPR_PFCWE, pctrl->base + regs->pwpr); /* BOWI=0, PFCWE=1 */
+ }
+}
+
static const struct rzg2l_hwcfg rzg2l_hwcfg = {
.regs = {
.pwpr = 0x3014,
@@ -2608,6 +2615,7 @@ static struct rzg2l_pinctrl_data r9a07g043_data = {
.variable_pin_cfg = r9a07g043f_variable_pin_cfg,
.n_variable_pin_cfg = ARRAY_SIZE(r9a07g043f_variable_pin_cfg),
#endif
+ .pwpr_pfc_lock_unlock = &rzg2l_pwpr_pfc_lock_unlock,
};

static struct rzg2l_pinctrl_data r9a07g044_data = {
@@ -2619,6 +2627,7 @@ static struct rzg2l_pinctrl_data r9a07g044_data = {
.n_dedicated_pins = ARRAY_SIZE(rzg2l_dedicated_pins.common) +
ARRAY_SIZE(rzg2l_dedicated_pins.rzg2l_pins),
.hwcfg = &rzg2l_hwcfg,
+ .pwpr_pfc_lock_unlock = &rzg2l_pwpr_pfc_lock_unlock,
};

static struct rzg2l_pinctrl_data r9a08g045_data = {
@@ -2629,6 +2638,7 @@ static struct rzg2l_pinctrl_data r9a08g045_data = {
.n_port_pins = ARRAY_SIZE(r9a08g045_gpio_configs) * RZG2L_PINS_PER_PORT,
.n_dedicated_pins = ARRAY_SIZE(rzg3s_dedicated_pins),
.hwcfg = &rzg3s_hwcfg,
+ .pwpr_pfc_lock_unlock = &rzg2l_pwpr_pfc_lock_unlock,
};

static const struct of_device_id rzg2l_pinctrl_of_table[] = {
--
2.34.1