From 3853f19ad79006aa8856fded30491cc13f98ecf1 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Mon, 6 Sep 2021 06:39:41 +0200 Subject: [PATCH 2/2] WIP: gpio: tegra186: Support multiple interrupts per bank Tegra194 and later support more than a single interrupt per bank. This is primarily useful for virtualization but can also be helpful for more fine-grained CPU affinity control. To keep things simple for now, route all pins to the first interrupt. For backwards-compatibility, support old device trees that specify only one interrupt per bank by counting the interrupts at probe time. Signed-off-by: Thierry Reding --- drivers/gpio/gpio-tegra186.c | 48 ++++++++++++++++++++++++++++++------ 1 file changed, 41 insertions(+), 7 deletions(-) diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c index 7cb0222ecee8..266c33df0343 100644 --- a/drivers/gpio/gpio-tegra186.c +++ b/drivers/gpio/gpio-tegra186.c @@ -69,6 +69,8 @@ struct tegra_gpio_soc { const char *name; unsigned int instance; + unsigned int num_irqs_per_bank; + const struct tegra186_pin_range *pin_ranges; unsigned int num_pin_ranges; const char *pinmux; @@ -452,7 +454,7 @@ static void tegra186_gpio_irq(struct irq_desc *desc) struct irq_domain *domain = gpio->gpio.irq.domain; struct irq_chip *chip = irq_desc_get_chip(desc); unsigned int parent = irq_desc_get_irq(desc); - unsigned int i, offset = 0; + unsigned int i, j, offset = 0; chained_irq_enter(chip, desc); @@ -465,7 +467,12 @@ static void tegra186_gpio_irq(struct irq_desc *desc) base = gpio->base + port->bank * 0x1000 + port->port * 0x200; /* skip ports that are not associated with this bank */ - if (parent != gpio->irq[port->bank]) + for (j = 0; j < gpio->num_irqs_per_bank; j++) { + if (parent != gpio->irq[port->bank * gpio->num_irqs_per_bank + j]) + break; + } + + if (j == gpio->num_irqs_per_bank) goto skip; value = readl(base + TEGRA186_GPIO_INTERRUPT_STATUS(1)); @@ -567,6 +574,7 @@ static const struct of_device_id tegra186_pmc_of_match[] = { static void tegra186_gpio_init_route_mapping(struct tegra_gpio *gpio) { + struct device *dev = gpio->gpio.parent; unsigned int i, j; u32 value; @@ -585,12 +593,30 @@ static void tegra186_gpio_init_route_mapping(struct tegra_gpio *gpio) */ if ((value & TEGRA186_GPIO_CTL_SCR_SEC_REN) == 0 && (value & TEGRA186_GPIO_CTL_SCR_SEC_WEN) == 0) { - for (j = 0; j < 8; j++) { + /* + * On Tegra194 and later, each pin can be routed to one or more + * interrupts. + */ + for (j = 0; j < gpio->num_irqs_per_bank; j++) { + dev_dbg(dev, "programming default interrupt routing for port %s\n", + port->name); + offset = TEGRA186_GPIO_INT_ROUTE_MAPPING(p, j); - value = readl(base + offset); - value = BIT(port->pins) - 1; - writel(value, base + offset); + /* + * By default we only want to route GPIO pins to IRQ 0. This works + * only under the assumption that we're running as the host kernel + * and hence all GPIO pins are owned by Linux. + * + * For cases where Linux is the guest OS, the hypervisor will have + * to configure the interrupt routing and pass only the valid + * interrupts via device tree. + */ + if (j == 0) { + value = readl(base + offset); + value = BIT(port->pins) - 1; + writel(value, base + offset); + } } } } @@ -610,6 +636,9 @@ static unsigned int tegra186_gpio_irqs_per_bank(struct tegra_gpio *gpio) gpio->num_irqs_per_bank = gpio->num_irq / gpio->num_banks; + if (gpio->num_irqs_per_bank > gpio->soc->num_irqs_per_bank) + goto error; + return 0; error: @@ -766,7 +795,8 @@ static int tegra186_gpio_probe(struct platform_device *pdev) irq->parents = gpio->irq; } - tegra186_gpio_init_route_mapping(gpio); + if (gpio->soc->num_irqs_per_bank > 1) + tegra186_gpio_init_route_mapping(gpio); np = of_find_matching_node(NULL, tegra186_pmc_of_match); if (np) { @@ -833,6 +863,7 @@ static const struct tegra_gpio_soc tegra186_main_soc = { .ports = tegra186_main_ports, .name = "tegra186-gpio", .instance = 0, + .num_irqs_per_bank = 1, }; #define TEGRA186_AON_GPIO_PORT(_name, _bank, _port, _pins) \ @@ -859,6 +890,7 @@ static const struct tegra_gpio_soc tegra186_aon_soc = { .ports = tegra186_aon_ports, .name = "tegra186-gpio-aon", .instance = 1, + .num_irqs_per_bank = 1, }; #define TEGRA194_MAIN_GPIO_PORT(_name, _bank, _port, _pins) \ @@ -910,6 +942,7 @@ static const struct tegra_gpio_soc tegra194_main_soc = { .ports = tegra194_main_ports, .name = "tegra194-gpio", .instance = 0, + .num_irqs_per_bank = 8, .num_pin_ranges = ARRAY_SIZE(tegra194_main_pin_ranges), .pin_ranges = tegra194_main_pin_ranges, .pinmux = "nvidia,tegra194-pinmux", @@ -936,6 +969,7 @@ static const struct tegra_gpio_soc tegra194_aon_soc = { .ports = tegra194_aon_ports, .name = "tegra194-gpio-aon", .instance = 1, + .num_irqs_per_bank = 8, }; static const struct of_device_id tegra186_gpio_of_match[] = { -- 2.33.0