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-rw-r--r--drivers/gpio/gpio-aspeed.c251
1 files changed, 231 insertions, 20 deletions
diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index b3968f66b1d2..1e00f4045f9d 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -12,6 +12,7 @@
#include <asm/div64.h>
#include <linux/clk.h>
#include <linux/gpio/driver.h>
+#include <linux/gpio/aspeed.h>
#include <linux/hashtable.h>
#include <linux/init.h>
#include <linux/io.h>
@@ -22,6 +23,15 @@
#include <linux/spinlock.h>
#include <linux/string.h>
+/*
+ * These two headers aren't meant to be used by GPIO drivers. We need
+ * them in order to access gpio_chip_hwgpio() which we need to implement
+ * the aspeed specific API which allows the coprocessor to request
+ * access to some GPIOs and to arbitrate between coprocessor and ARM.
+ */
+#include <linux/gpio/consumer.h>
+#include "gpiolib.h"
+
struct aspeed_bank_props {
unsigned int bank;
u32 input;
@@ -56,6 +66,7 @@ struct aspeed_gpio {
struct clk *clk;
u32 *dcache;
+ u8 *cf_copro_bankmap;
};
struct aspeed_gpio_bank {
@@ -83,6 +94,9 @@ struct aspeed_gpio_bank {
static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
+static const struct aspeed_gpio_copro_ops *copro_ops;
+static void *copro_data;
+
static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
{
.val_regs = 0x0000,
@@ -323,6 +337,50 @@ static void aspeed_gpio_change_cmd_source(struct aspeed_gpio *gpio,
iowrite32(reg, c0);
}
+static bool aspeed_gpio_copro_request(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+ if (!copro_ops || !gpio->cf_copro_bankmap)
+ return false;
+ if (!gpio->cf_copro_bankmap[offset >> 3])
+ return false;
+ if (!copro_ops->request_access)
+ return false;
+
+ /* Pause the coprocessor */
+ copro_ops->request_access(copro_data);
+
+ /* Change command source back to ARM */
+ aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3, GPIO_CMDSRC_ARM);
+
+ /* Update cache */
+ gpio->dcache[GPIO_BANK(offset)] = ioread32(bank_reg(gpio, bank, reg_rdata));
+
+ return true;
+}
+
+static void aspeed_gpio_copro_release(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+ if (!copro_ops || !gpio->cf_copro_bankmap)
+ return;
+ if (!gpio->cf_copro_bankmap[offset >> 3])
+ return;
+ if (!copro_ops->release_access)
+ return;
+
+ /* Change command source back to ColdFire */
+ aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3,
+ GPIO_CMDSRC_COLDFIRE);
+
+ /* Restart the coprocessor */
+ copro_ops->release_access(copro_data);
+}
+
static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
@@ -356,11 +414,15 @@ static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
unsigned long flags;
+ bool copro;
spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
__aspeed_gpio_set(gc, offset, val);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
}
@@ -368,7 +430,9 @@ static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
+ void __iomem *addr = bank_reg(gpio, bank, reg_dir);
unsigned long flags;
+ bool copro;
u32 reg;
if (!have_input(gpio, offset))
@@ -376,8 +440,13 @@ static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
spin_lock_irqsave(&gpio->lock, flags);
- reg = ioread32(bank_reg(gpio, bank, reg_dir));
- iowrite32(reg & ~GPIO_BIT(offset), bank_reg(gpio, bank, reg_dir));
+ reg = ioread32(addr);
+ reg &= ~GPIO_BIT(offset);
+
+ copro = aspeed_gpio_copro_request(gpio, offset);
+ iowrite32(reg, addr);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
@@ -389,7 +458,9 @@ static int aspeed_gpio_dir_out(struct gpio_chip *gc,
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
+ void __iomem *addr = bank_reg(gpio, bank, reg_dir);
unsigned long flags;
+ bool copro;
u32 reg;
if (!have_output(gpio, offset))
@@ -397,10 +468,15 @@ static int aspeed_gpio_dir_out(struct gpio_chip *gc,
spin_lock_irqsave(&gpio->lock, flags);
+ reg = ioread32(addr);
+ reg |= GPIO_BIT(offset);
+
+ copro = aspeed_gpio_copro_request(gpio, offset);
__aspeed_gpio_set(gc, offset, val);
- reg = ioread32(bank_reg(gpio, bank, reg_dir));
- iowrite32(reg | GPIO_BIT(offset), bank_reg(gpio, bank, reg_dir));
+ iowrite32(reg, addr);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
return 0;
@@ -430,24 +506,23 @@ static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
}
static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
- struct aspeed_gpio **gpio,
- const struct aspeed_gpio_bank **bank,
- u32 *bit)
+ struct aspeed_gpio **gpio,
+ const struct aspeed_gpio_bank **bank,
+ u32 *bit, int *offset)
{
- int offset;
struct aspeed_gpio *internal;
- offset = irqd_to_hwirq(d);
+ *offset = irqd_to_hwirq(d);
internal = irq_data_get_irq_chip_data(d);
/* This might be a bit of a questionable place to check */
- if (!have_irq(internal, offset))
+ if (!have_irq(internal, *offset))
return -ENOTSUPP;
*gpio = internal;
- *bank = to_bank(offset);
- *bit = GPIO_BIT(offset);
+ *bank = to_bank(*offset);
+ *bit = GPIO_BIT(*offset);
return 0;
}
@@ -458,17 +533,23 @@ static void aspeed_gpio_irq_ack(struct irq_data *d)
struct aspeed_gpio *gpio;
unsigned long flags;
void __iomem *status_addr;
+ int rc, offset;
+ bool copro;
u32 bit;
- int rc;
- rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return;
status_addr = bank_reg(gpio, bank, reg_irq_status);
spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
iowrite32(bit, status_addr);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
}
@@ -479,15 +560,17 @@ static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
unsigned long flags;
u32 reg, bit;
void __iomem *addr;
- int rc;
+ int rc, offset;
+ bool copro;
- rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return;
addr = bank_reg(gpio, bank, reg_irq_enable);
spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
reg = ioread32(addr);
if (set)
@@ -496,6 +579,8 @@ static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
reg &= ~bit;
iowrite32(reg, addr);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
}
@@ -520,9 +605,10 @@ static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
struct aspeed_gpio *gpio;
unsigned long flags;
void __iomem *addr;
- int rc;
+ int rc, offset;
+ bool copro;
- rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return -EINVAL;
@@ -548,6 +634,7 @@ static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
}
spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
addr = bank_reg(gpio, bank, reg_irq_type0);
reg = ioread32(addr);
@@ -564,6 +651,8 @@ static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
reg = (reg & ~bit) | type2;
iowrite32(reg, addr);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
irq_set_handler_locked(d, handler);
@@ -658,11 +747,14 @@ static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *treg;
+ bool copro;
u32 val;
treg = bank_reg(gpio, to_bank(offset), reg_tolerance);
spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
val = readl(treg);
if (enable)
@@ -671,6 +763,9 @@ static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
val &= ~GPIO_BIT(offset);
writel(val, treg);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
spin_unlock_irqrestore(&gpio->lock, flags);
return 0;
@@ -766,6 +861,9 @@ static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset,
void __iomem *addr;
u32 val;
+ /* Note: Debounce timer isn't under control of the command
+ * source registers, so no need to sync with the coprocessor
+ */
addr = bank_reg(gpio, bank, reg_debounce_sel1);
val = ioread32(addr);
iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr);
@@ -912,6 +1010,111 @@ static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
return -ENOTSUPP;
}
+/**
+ * aspeed_gpio_copro_set_ops - Sets the callbacks used for handhsaking with
+ * the coprocessor for shared GPIO banks
+ * @ops: The callbacks
+ * @data: Pointer passed back to the callbacks
+ */
+int aspeed_gpio_copro_set_ops(const struct aspeed_gpio_copro_ops *ops, void *data)
+{
+ copro_data = data;
+ copro_ops = ops;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_set_ops);
+
+/**
+ * aspeed_gpio_copro_grab_gpio - Mark a GPIO used by the coprocessor. The entire
+ * bank gets marked and any access from the ARM will
+ * result in handshaking via callbacks.
+ * @desc: The GPIO to be marked
+ * @vreg_offset: If non-NULL, returns the value register offset in the GPIO space
+ * @dreg_offset: If non-NULL, returns the data latch register offset in the GPIO space
+ * @bit: If non-NULL, returns the bit number of the GPIO in the registers
+ */
+int aspeed_gpio_copro_grab_gpio(struct gpio_desc *desc,
+ u16 *vreg_offset, u16 *dreg_offset, u8 *bit)
+{
+ struct gpio_chip *chip = gpiod_to_chip(desc);
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned long flags;
+
+ if (!gpio->cf_copro_bankmap)
+ gpio->cf_copro_bankmap = kzalloc(gpio->config->nr_gpios >> 3, GFP_KERNEL);
+ if (!gpio->cf_copro_bankmap)
+ return -ENOMEM;
+ if (offset < 0 || offset > gpio->config->nr_gpios)
+ return -EINVAL;
+ bindex = offset >> 3;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ /* Sanity check, this shouldn't happen */
+ if (gpio->cf_copro_bankmap[bindex] == 0xff) {
+ rc = -EIO;
+ goto bail;
+ }
+ gpio->cf_copro_bankmap[bindex]++;
+
+ /* Switch command source */
+ if (gpio->cf_copro_bankmap[bindex] == 1)
+ aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+ GPIO_CMDSRC_COLDFIRE);
+
+ if (vreg_offset)
+ *vreg_offset = bank->val_regs;
+ if (dreg_offset)
+ *dreg_offset = bank->rdata_reg;
+ if (bit)
+ *bit = GPIO_OFFSET(offset);
+ bail:
+ spin_unlock_irqrestore(&gpio->lock, flags);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_grab_gpio);
+
+/**
+ * aspeed_gpio_copro_release_gpio - Unmark a GPIO used by the coprocessor.
+ * @desc: The GPIO to be marked
+ */
+int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
+{
+ struct gpio_chip *chip = gpiod_to_chip(desc);
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned long flags;
+
+ if (!gpio->cf_copro_bankmap)
+ return -ENXIO;
+
+ if (offset < 0 || offset > gpio->config->nr_gpios)
+ return -EINVAL;
+ bindex = offset >> 3;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ /* Sanity check, this shouldn't happen */
+ if (gpio->cf_copro_bankmap[bindex] == 0) {
+ rc = -EIO;
+ goto bail;
+ }
+ gpio->cf_copro_bankmap[bindex]--;
+
+ /* Switch command source */
+ if (gpio->cf_copro_bankmap[bindex] == 0)
+ aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+ GPIO_CMDSRC_ARM);
+ bail:
+ spin_unlock_irqrestore(&gpio->lock, flags);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);
+
/*
* Any banks not specified in a struct aspeed_bank_props array are assumed to
* have the properties:
@@ -1002,10 +1205,18 @@ static int __init aspeed_gpio_probe(struct platform_device *pdev)
if (!gpio->dcache)
return -ENOMEM;
- /* Populate it with initial values read from the HW */
+ /*
+ * Populate it with initial values read from the HW and switch
+ * all command sources to the ARM by default
+ */
for (i = 0; i < banks; i++) {
- void __iomem *addr = bank_reg(gpio, &aspeed_gpio_banks[i], reg_rdata);
+ const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
+ void __iomem *addr = bank_reg(gpio, bank, reg_rdata);
gpio->dcache[i] = ioread32(addr);
+ aspeed_gpio_change_cmd_source(gpio, bank, 0, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 1, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 2, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 3, GPIO_CMDSRC_ARM);
}
rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 09:06:53 +0100