diff options
author | Dan O'Donovan | 2016-06-10 13:23:34 +0100 |
---|---|---|
committer | Linus Walleij | 2016-06-15 08:37:39 +0200 |
commit | 0bd50d719b004110e791800450ad204399100a86 (patch) | |
tree | 66e7d62be093590ebee00f7c148b1cf15b0230cd | |
parent | 38c1e5e7b91dfa82547657269cabf5fba66c7a2b (diff) |
pinctrl: cherryview: prevent concurrent access to GPIO controllers
Due to a silicon issue on the Atom X5-Z8000 "Cherry Trail" processor
series, a common lock must be used to prevent concurrent accesses
across the 4 GPIO controllers managed by this driver.
See Intel Atom Z8000 Processor Series Specification Update
(Rev. 005), errata #CHT34, for further information.
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Dan O'Donovan <dan@emutex.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
-rw-r--r-- | drivers/pinctrl/intel/pinctrl-cherryview.c | 80 |
1 files changed, 44 insertions, 36 deletions
diff --git a/drivers/pinctrl/intel/pinctrl-cherryview.c b/drivers/pinctrl/intel/pinctrl-cherryview.c index ac4f564f1c3e..bf65c948b31d 100644 --- a/drivers/pinctrl/intel/pinctrl-cherryview.c +++ b/drivers/pinctrl/intel/pinctrl-cherryview.c @@ -160,7 +160,6 @@ struct chv_pin_context { * @pctldev: Pointer to the pin controller device * @chip: GPIO chip in this pin controller * @regs: MMIO registers - * @lock: Lock to serialize register accesses * @intr_lines: Stores mapping between 16 HW interrupt wires and GPIO * offset (in GPIO number space) * @community: Community this pinctrl instance represents @@ -174,7 +173,6 @@ struct chv_pinctrl { struct pinctrl_dev *pctldev; struct gpio_chip chip; void __iomem *regs; - raw_spinlock_t lock; unsigned intr_lines[16]; const struct chv_community *community; u32 saved_intmask; @@ -657,6 +655,17 @@ static const struct chv_community *chv_communities[] = { &southeast_community, }; +/* + * Lock to serialize register accesses + * + * Due to a silicon issue, a shared lock must be used to prevent + * concurrent accesses across the 4 GPIO controllers. + * + * See Intel Atom Z8000 Processor Series Specification Update (Rev. 005), + * errata #CHT34, for further information. + */ +static DEFINE_RAW_SPINLOCK(chv_lock); + static void __iomem *chv_padreg(struct chv_pinctrl *pctrl, unsigned offset, unsigned reg) { @@ -718,13 +727,13 @@ static void chv_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s, u32 ctrl0, ctrl1; bool locked; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0)); ctrl1 = readl(chv_padreg(pctrl, offset, CHV_PADCTRL1)); locked = chv_pad_locked(pctrl, offset); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); if (ctrl0 & CHV_PADCTRL0_GPIOEN) { seq_puts(s, "GPIO "); @@ -787,14 +796,14 @@ static int chv_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned function, grp = &pctrl->community->groups[group]; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); /* Check first that the pad is not locked */ for (i = 0; i < grp->npins; i++) { if (chv_pad_locked(pctrl, grp->pins[i])) { dev_warn(pctrl->dev, "unable to set mode for locked pin %u\n", grp->pins[i]); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return -EBUSY; } } @@ -837,7 +846,7 @@ static int chv_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned function, pin, altfunc->mode, altfunc->invert_oe ? "" : "not "); } - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return 0; } @@ -851,13 +860,13 @@ static int chv_gpio_request_enable(struct pinctrl_dev *pctldev, void __iomem *reg; u32 value; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); if (chv_pad_locked(pctrl, offset)) { value = readl(chv_padreg(pctrl, offset, CHV_PADCTRL0)); if (!(value & CHV_PADCTRL0_GPIOEN)) { /* Locked so cannot enable */ - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return -EBUSY; } } else { @@ -897,7 +906,7 @@ static int chv_gpio_request_enable(struct pinctrl_dev *pctldev, chv_writel(value, reg); } - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return 0; } @@ -911,13 +920,13 @@ static void chv_gpio_disable_free(struct pinctrl_dev *pctldev, void __iomem *reg; u32 value; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); reg = chv_padreg(pctrl, offset, CHV_PADCTRL0); value = readl(reg) & ~CHV_PADCTRL0_GPIOEN; chv_writel(value, reg); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); } static int chv_gpio_set_direction(struct pinctrl_dev *pctldev, @@ -929,7 +938,7 @@ static int chv_gpio_set_direction(struct pinctrl_dev *pctldev, unsigned long flags; u32 ctrl0; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(reg) & ~CHV_PADCTRL0_GPIOCFG_MASK; if (input) @@ -938,7 +947,7 @@ static int chv_gpio_set_direction(struct pinctrl_dev *pctldev, ctrl0 |= CHV_PADCTRL0_GPIOCFG_GPO << CHV_PADCTRL0_GPIOCFG_SHIFT; chv_writel(ctrl0, reg); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return 0; } @@ -963,10 +972,10 @@ static int chv_config_get(struct pinctrl_dev *pctldev, unsigned pin, u16 arg = 0; u32 term; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); ctrl1 = readl(chv_padreg(pctrl, pin, CHV_PADCTRL1)); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); term = (ctrl0 & CHV_PADCTRL0_TERM_MASK) >> CHV_PADCTRL0_TERM_SHIFT; @@ -1040,7 +1049,7 @@ static int chv_config_set_pull(struct chv_pinctrl *pctrl, unsigned pin, unsigned long flags; u32 ctrl0, pull; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(reg); switch (param) { @@ -1063,7 +1072,7 @@ static int chv_config_set_pull(struct chv_pinctrl *pctrl, unsigned pin, pull = CHV_PADCTRL0_TERM_20K << CHV_PADCTRL0_TERM_SHIFT; break; default: - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return -EINVAL; } @@ -1081,7 +1090,7 @@ static int chv_config_set_pull(struct chv_pinctrl *pctrl, unsigned pin, pull = CHV_PADCTRL0_TERM_20K << CHV_PADCTRL0_TERM_SHIFT; break; default: - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return -EINVAL; } @@ -1089,12 +1098,12 @@ static int chv_config_set_pull(struct chv_pinctrl *pctrl, unsigned pin, break; default: - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return -EINVAL; } chv_writel(ctrl0, reg); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return 0; } @@ -1160,9 +1169,9 @@ static int chv_gpio_get(struct gpio_chip *chip, unsigned offset) unsigned long flags; u32 ctrl0, cfg; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); cfg = ctrl0 & CHV_PADCTRL0_GPIOCFG_MASK; cfg >>= CHV_PADCTRL0_GPIOCFG_SHIFT; @@ -1180,7 +1189,7 @@ static void chv_gpio_set(struct gpio_chip *chip, unsigned offset, int value) void __iomem *reg; u32 ctrl0; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); reg = chv_padreg(pctrl, pin, CHV_PADCTRL0); ctrl0 = readl(reg); @@ -1192,7 +1201,7 @@ static void chv_gpio_set(struct gpio_chip *chip, unsigned offset, int value) chv_writel(ctrl0, reg); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); } static int chv_gpio_get_direction(struct gpio_chip *chip, unsigned offset) @@ -1202,9 +1211,9 @@ static int chv_gpio_get_direction(struct gpio_chip *chip, unsigned offset) u32 ctrl0, direction; unsigned long flags; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); ctrl0 = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); direction = ctrl0 & CHV_PADCTRL0_GPIOCFG_MASK; direction >>= CHV_PADCTRL0_GPIOCFG_SHIFT; @@ -1242,14 +1251,14 @@ static void chv_gpio_irq_ack(struct irq_data *d) int pin = chv_gpio_offset_to_pin(pctrl, irqd_to_hwirq(d)); u32 intr_line; - raw_spin_lock(&pctrl->lock); + raw_spin_lock(&chv_lock); intr_line = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); intr_line &= CHV_PADCTRL0_INTSEL_MASK; intr_line >>= CHV_PADCTRL0_INTSEL_SHIFT; chv_writel(BIT(intr_line), pctrl->regs + CHV_INTSTAT); - raw_spin_unlock(&pctrl->lock); + raw_spin_unlock(&chv_lock); } static void chv_gpio_irq_mask_unmask(struct irq_data *d, bool mask) @@ -1260,7 +1269,7 @@ static void chv_gpio_irq_mask_unmask(struct irq_data *d, bool mask) u32 value, intr_line; unsigned long flags; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); intr_line = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); intr_line &= CHV_PADCTRL0_INTSEL_MASK; @@ -1273,7 +1282,7 @@ static void chv_gpio_irq_mask_unmask(struct irq_data *d, bool mask) value |= BIT(intr_line); chv_writel(value, pctrl->regs + CHV_INTMASK); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); } static void chv_gpio_irq_mask(struct irq_data *d) @@ -1307,7 +1316,7 @@ static unsigned chv_gpio_irq_startup(struct irq_data *d) unsigned long flags; u32 intsel, value; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); intsel = readl(chv_padreg(pctrl, pin, CHV_PADCTRL0)); intsel &= CHV_PADCTRL0_INTSEL_MASK; intsel >>= CHV_PADCTRL0_INTSEL_SHIFT; @@ -1322,7 +1331,7 @@ static unsigned chv_gpio_irq_startup(struct irq_data *d) irq_set_handler_locked(d, handler); pctrl->intr_lines[intsel] = offset; } - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); } chv_gpio_irq_unmask(d); @@ -1338,7 +1347,7 @@ static int chv_gpio_irq_type(struct irq_data *d, unsigned type) unsigned long flags; u32 value; - raw_spin_lock_irqsave(&pctrl->lock, flags); + raw_spin_lock_irqsave(&chv_lock, flags); /* * Pins which can be used as shared interrupt are configured in @@ -1387,7 +1396,7 @@ static int chv_gpio_irq_type(struct irq_data *d, unsigned type) else if (type & IRQ_TYPE_LEVEL_MASK) irq_set_handler_locked(d, handle_level_irq); - raw_spin_unlock_irqrestore(&pctrl->lock, flags); + raw_spin_unlock_irqrestore(&chv_lock, flags); return 0; } @@ -1499,7 +1508,6 @@ static int chv_pinctrl_probe(struct platform_device *pdev) if (i == ARRAY_SIZE(chv_communities)) return -ENODEV; - raw_spin_lock_init(&pctrl->lock); pctrl->dev = &pdev->dev; #ifdef CONFIG_PM_SLEEP |