[PATCH v4] gpio: tegra186: Check GPIO pin permission before access.
From: Prathamesh Shete
Date: Wed May 24 2023 - 06:50:45 EST
This change checks if we have the necessary permission to
access the GPIO. For devices that have support for virtualisation
we need to check both the TEGRA186_GPIO_VM_REG and the
TEGRA186_GPIO_SCR_REG registers. For device that do not have
virtualisation support for GPIOs we only need to check the
TEGRA186_GPIO_SCR_REG register.
Signed-off-by: Manish Bhardwaj <mbhardwaj@xxxxxxxxxx>
Signed-off-by: Prathamesh Shete <pshete@xxxxxxxxxx>
Acked-by: Thierry Reding <treding@xxxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Acked-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
drivers/gpio/gpio-tegra186.c | 78 ++++++++++++++++++++++++++++++++++++
1 file changed, 78 insertions(+)
diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c
index b904de0b1784..464b0ea3b6f1 100644
--- a/drivers/gpio/gpio-tegra186.c
+++ b/drivers/gpio/gpio-tegra186.c
@@ -27,6 +27,22 @@
#define TEGRA186_GPIO_INT_ROUTE_MAPPING(p, x) (0x14 + (p) * 0x20 + (x) * 4)
+#define TEGRA186_GPIO_VM 0x00
+#define TEGRA186_GPIO_VM_RW_MASK 0x03
+#define TEGRA186_GPIO_SCR 0x04
+#define TEGRA186_GPIO_SCR_PIN_SIZE 0x08
+#define TEGRA186_GPIO_SCR_PORT_SIZE 0x40
+#define TEGRA186_GPIO_SCR_SEC_WEN BIT(28)
+#define TEGRA186_GPIO_SCR_SEC_REN BIT(27)
+#define TEGRA186_GPIO_SCR_SEC_G1W BIT(9)
+#define TEGRA186_GPIO_SCR_SEC_G1R BIT(1)
+#define TEGRA186_GPIO_FULL_ACCESS (TEGRA186_GPIO_SCR_SEC_WEN | \
+ TEGRA186_GPIO_SCR_SEC_REN | \
+ TEGRA186_GPIO_SCR_SEC_G1R | \
+ TEGRA186_GPIO_SCR_SEC_G1W)
+#define TEGRA186_GPIO_SCR_SEC_ENABLE (TEGRA186_GPIO_SCR_SEC_WEN | \
+ TEGRA186_GPIO_SCR_SEC_REN)
+
/* control registers */
#define TEGRA186_GPIO_ENABLE_CONFIG 0x00
#define TEGRA186_GPIO_ENABLE_CONFIG_ENABLE BIT(0)
@@ -81,6 +97,7 @@ struct tegra_gpio_soc {
unsigned int num_pin_ranges;
const char *pinmux;
bool has_gte;
+ bool has_vm_support;
};
struct tegra_gpio {
@@ -130,6 +147,58 @@ static void __iomem *tegra186_gpio_get_base(struct tegra_gpio *gpio,
return gpio->base + offset + pin * 0x20;
}
+static void __iomem *tegra186_gpio_get_secure_base(struct tegra_gpio *gpio,
+ unsigned int pin)
+{
+ const struct tegra_gpio_port *port;
+ unsigned int offset;
+
+ port = tegra186_gpio_get_port(gpio, &pin);
+ if (!port)
+ return NULL;
+
+ offset = port->bank * 0x1000 + port->port * TEGRA186_GPIO_SCR_PORT_SIZE;
+
+ return gpio->secure + offset + pin * TEGRA186_GPIO_SCR_PIN_SIZE;
+}
+
+static inline bool tegra186_gpio_is_accessible(struct tegra_gpio *gpio, unsigned int pin)
+{
+ void __iomem *secure;
+ u32 value;
+
+ secure = tegra186_gpio_get_secure_base(gpio, pin);
+
+ if (gpio->soc->has_vm_support) {
+ value = readl(secure + TEGRA186_GPIO_VM);
+ if ((value & TEGRA186_GPIO_VM_RW_MASK) != TEGRA186_GPIO_VM_RW_MASK)
+ return false;
+ }
+
+ value = __raw_readl(secure + TEGRA186_GPIO_SCR);
+
+ if ((value & TEGRA186_GPIO_SCR_SEC_ENABLE) == 0)
+ return true;
+
+ if ((value & TEGRA186_GPIO_FULL_ACCESS) == TEGRA186_GPIO_FULL_ACCESS)
+ return true;
+
+ return false;
+}
+
+static int tegra186_init_valid_mask(struct gpio_chip *chip,
+ unsigned long *valid_mask, unsigned int ngpios)
+{
+ struct tegra_gpio *gpio = gpiochip_get_data(chip);
+ unsigned int j;
+
+ for (j = 0; j < ngpios; j++) {
+ if (!tegra186_gpio_is_accessible(gpio, j))
+ clear_bit(j, valid_mask);
+ }
+ return 0;
+}
+
static int tegra186_gpio_get_direction(struct gpio_chip *chip,
unsigned int offset)
{
@@ -816,6 +885,7 @@ static int tegra186_gpio_probe(struct platform_device *pdev)
gpio->gpio.set = tegra186_gpio_set;
gpio->gpio.set_config = tegra186_gpio_set_config;
gpio->gpio.add_pin_ranges = tegra186_gpio_add_pin_ranges;
+ gpio->gpio.init_valid_mask = tegra186_init_valid_mask;
if (gpio->soc->has_gte) {
gpio->gpio.en_hw_timestamp = tegra186_gpio_en_hw_ts;
gpio->gpio.dis_hw_timestamp = tegra186_gpio_dis_hw_ts;
@@ -958,6 +1028,7 @@ static const struct tegra_gpio_soc tegra186_main_soc = {
.name = "tegra186-gpio",
.instance = 0,
.num_irqs_per_bank = 1,
+ .has_vm_support = false,
};
#define TEGRA186_AON_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -985,6 +1056,7 @@ static const struct tegra_gpio_soc tegra186_aon_soc = {
.name = "tegra186-gpio-aon",
.instance = 1,
.num_irqs_per_bank = 1,
+ .has_vm_support = false,
};
#define TEGRA194_MAIN_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1040,6 +1112,7 @@ static const struct tegra_gpio_soc tegra194_main_soc = {
.num_pin_ranges = ARRAY_SIZE(tegra194_main_pin_ranges),
.pin_ranges = tegra194_main_pin_ranges,
.pinmux = "nvidia,tegra194-pinmux",
+ .has_vm_support = true,
};
#define TEGRA194_AON_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1065,6 +1138,7 @@ static const struct tegra_gpio_soc tegra194_aon_soc = {
.instance = 1,
.num_irqs_per_bank = 8,
.has_gte = true,
+ .has_vm_support = false,
};
#define TEGRA234_MAIN_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1109,6 +1183,7 @@ static const struct tegra_gpio_soc tegra234_main_soc = {
.name = "tegra234-gpio",
.instance = 0,
.num_irqs_per_bank = 8,
+ .has_vm_support = true,
};
#define TEGRA234_AON_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1135,6 +1210,7 @@ static const struct tegra_gpio_soc tegra234_aon_soc = {
.instance = 1,
.num_irqs_per_bank = 8,
.has_gte = true,
+ .has_vm_support = false,
};
#define TEGRA241_MAIN_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1165,6 +1241,7 @@ static const struct tegra_gpio_soc tegra241_main_soc = {
.name = "tegra241-gpio",
.instance = 0,
.num_irqs_per_bank = 8,
+ .has_vm_support = false,
};
#define TEGRA241_AON_GPIO_PORT(_name, _bank, _port, _pins) \
@@ -1186,6 +1263,7 @@ static const struct tegra_gpio_soc tegra241_aon_soc = {
.name = "tegra241-gpio-aon",
.instance = 1,
.num_irqs_per_bank = 8,
+ .has_vm_support = false,
};
static const struct of_device_id tegra186_gpio_of_match[] = {
--
2.17.1