diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 36208e93d745..59c4ee8109dd 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -28,25 +28,35 @@ * DOC: Overview * * gmux is a microcontroller built into the MacBook Pro to support dual GPUs: - * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on retinas. + * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on pre-T2 retinas. + * + * On T2 Macbooks, the gmux is part of the T2 Coprocessor's SMC. The SMC has + * an I2C connection to a `NXP PCAL6524` GPIO expander, which enables/disables + * the voltage regulators of the discrete GPU, drives the display panel power, + * and has a GPIO to switch the eDP mux. The Intel CPU can interact with + * gmux through MMIO, similar to how the main SMC interface is controlled. * * (The MacPro6,1 2013 also has a gmux, however it is unclear why since it has * dual GPUs but no built-in display.) * * gmux is connected to the LPC bus of the southbridge. Its I/O ports are * accessed differently depending on the microcontroller: Driver functions - * to access a pre-retina gmux are infixed ``_pio_``, those for a retina gmux - * are infixed ``_index_``. + * to access a pre-retina gmux are infixed ``_pio_``, those for a pre-T2 + * retina gmux are infixed ``_index_``, and those on T2 Macs are infixed + * with ``_mmio_``. * * .. _Lattice XP2: * http://www.latticesemi.com/en/Products/FPGAandCPLD/LatticeXP2.aspx * .. _Renesas R4F2113: * http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jsp + * .. _NXP PCAL6524: + * https://www.nxp.com/docs/en/data-sheet/PCAL6524.pdf */ struct apple_gmux_config; struct apple_gmux_data { + u8 *__iomem iomem_base; unsigned long iostart; unsigned long iolen; const struct apple_gmux_config *config; @@ -208,6 +218,79 @@ static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, mutex_unlock(&gmux_data->index_lock); } +static int gmux_mmio_wait(struct apple_gmux_data *gmux_data) +{ + int i = 200; + u8 gwr = ioread8(gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + + while (i && gwr) { + gwr = ioread8(gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + udelay(100); + i--; + } + + return !!i; +} + +static u8 gmux_mmio_read8(struct apple_gmux_data *gmux_data, int port) +{ + u8 val; + + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8((port & 0xff), gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_READ | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + val = ioread8(gmux_data->iomem_base); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_mmio_write8(struct apple_gmux_data *gmux_data, int port, + u8 val) +{ + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8(val, gmux_data->iomem_base); + + iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_WRITE | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + + gmux_mmio_wait(gmux_data); + mutex_unlock(&gmux_data->index_lock); +} + +static u32 gmux_mmio_read32(struct apple_gmux_data *gmux_data, int port) +{ + u32 val; + + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8((port & 0xff), gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_READ | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + val = be32_to_cpu(ioread32(gmux_data->iomem_base)); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_mmio_write32(struct apple_gmux_data *gmux_data, int port, + u32 val) +{ + mutex_lock(&gmux_data->index_lock); + iowrite32(cpu_to_be32(val), gmux_data->iomem_base); + iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_WRITE | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + mutex_unlock(&gmux_data->index_lock); +} + static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port) { return gmux_data->config->read8(gmux_data, port); @@ -236,8 +319,8 @@ static void gmux_write32(struct apple_gmux_data *gmux_data, int port, * the GPU. On dual GPU MacBook Pros by contrast, either GPU may be suspended * to conserve energy. Hence the PWM signal needs to be generated by a separate * backlight driver which is controlled by gmux. The earliest generation - * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. All newer models - * use a `TI LP8545`_. + * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. Newer models + * use a `TI LP8545`_ or a TI LP8548. * * .. _TI LP8543: https://www.ti.com/lit/ds/symlink/lp8543.pdf * .. _TI LP8545: https://www.ti.com/lit/ds/symlink/lp8545.pdf @@ -301,8 +384,8 @@ static const struct backlight_ops gmux_bl_ops = { * connecting it either to the discrete GPU or the Thunderbolt controller. * Oddly enough, while the full port is no longer switchable, AUX and HPD * are still switchable by way of an `NXP CBTL03062`_ (on pre-retinas - * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on retinas) under the - * control of gmux. Since the integrated GPU is missing the main link, + * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on pre-t2 retinas) under + * the control of gmux. Since the integrated GPU is missing the main link, * external displays appear to it as phantoms which fail to link-train. * * gmux receives the HPD signal of all display connectors and sends an @@ -503,14 +586,42 @@ static const struct apple_gmux_config apple_gmux_index = { .name = "indexed" }; +static const struct apple_gmux_config apple_gmux_mmio = { + .read8 = &gmux_mmio_read8, + .write8 = &gmux_mmio_write8, + .read32 = &gmux_mmio_read32, + .write32 = &gmux_mmio_write32, + .gmux_handler = &gmux_handler_no_ddc, + .handler_flags = VGA_SWITCHEROO_NEEDS_EDP_CONFIG, + .resource_type = IORESOURCE_MEM, + .read_version_as_u32 = true, + .name = "T2" +}; + + /** * DOC: Interrupt * * gmux is also connected to a GPIO pin of the southbridge and thereby is able - * to trigger an ACPI GPE. On the MBP5 2008/09 it's GPIO pin 22 of the Nvidia - * MCP79, on all following generations it's GPIO pin 6 of the Intel PCH. + * to trigger an ACPI GPE. ACPI name GMGP holds this GPIO pin's number. On the + * MBP5 2008/09 it's GPIO pin 22 of the Nvidia MCP79, on following generations + * it's GPIO pin 6 of the Intel PCH, on MMIO gmux's it's pin 21. + * * The GPE merely signals that an interrupt occurred, the actual type of event * is identified by reading a gmux register. + * + * In addition to the GMGP name, gmux's ACPI device also has two methods GMSP + * and GMLV. GMLV likely means "GMUX Level", and reads the value of the GPIO, + * while GMSP likely means "GMUX Set Polarity", and seems to write to the GPIO's + * value. On newer Macbooks (This was introduced with or sometime before the + * MacBookPro14,3), the ACPI GPE method differentiates between the OS type: On + * Darwin, only a notification is signaled, whereas on other OSes, the GPIO's + * value is read and then inverted. + * + * Because Linux masquerades as Darwin, it ends up in the notification-only code + * path. On MMIO gmux's, this seems to lead to us being unable to clear interrupts, + * unless we call GMSP(0). Without this, there is a flood of status=0 interrupts + * that can't be cleared. This issue seems to be unique to MMIO gmux's. */ static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data) @@ -537,6 +648,9 @@ static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data) /* to clear interrupts write back current status */ status = gmux_interrupt_get_status(gmux_data); gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status); + /* Prevent flood of status=0 interrupts */ + if (gmux_data->config == &apple_gmux_mmio) + acpi_execute_simple_method(gmux_data->dhandle, "GMSP", 0); } static void gmux_notify_handler(acpi_handle device, u32 value, void *context) @@ -609,6 +723,25 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) pnp_set_drvdata(pnp, gmux_data); switch (type) { + case APPLE_GMUX_TYPE_MMIO: + gmux_data->config = &apple_gmux_mmio; + mutex_init(&gmux_data->index_lock); + + res = pnp_get_resource(pnp, IORESOURCE_MEM, 0); + gmux_data->iostart = res->start; + /* Although the ACPI table only allocates 8 bytes, we need 16. */ + gmux_data->iolen = 16; + if (!request_mem_region(gmux_data->iostart, gmux_data->iolen, + "Apple gmux")) { + pr_err("gmux I/O already in use\n"); + goto err_free; + } + gmux_data->iomem_base = ioremap(gmux_data->iostart, gmux_data->iolen); + if (!gmux_data->iomem_base) { + pr_err("couldn't remap gmux mmio region"); + goto err_release; + } + goto get_version; case APPLE_GMUX_TYPE_INDEXED: gmux_data->config = &apple_gmux_index; mutex_init(&gmux_data->index_lock); @@ -628,6 +761,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) goto err_free; } +get_version: if (gmux_data->config->read_version_as_u32) { version = gmux_read32(gmux_data, GMUX_PORT_VERSION_MAJOR); ver_major = (version >> 24) & 0xff; @@ -658,7 +792,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) gmux_data, &gmux_bl_ops, &props); if (IS_ERR(bdev)) { ret = PTR_ERR(bdev); - goto err_release; + goto err_unmap; } gmux_data->bdev = bdev; @@ -725,7 +859,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) /* * Retina MacBook Pros cannot switch the panel's AUX separately * and need eDP pre-calibration. They are distinguishable from - * pre-retinas by having an "indexed" gmux. + * pre-retinas by having an "indexed" or "T2" gmux. * * Pre-retina MacBook Pros can switch the panel's DDC separately. */ @@ -750,8 +884,14 @@ err_enable_gpe: &gmux_notify_handler); err_notify: backlight_device_unregister(bdev); +err_unmap: + if (gmux_data->iomem_base) + iounmap(gmux_data->iomem_base); err_release: - release_region(gmux_data->iostart, gmux_data->iolen); + if (gmux_data->config->resource_type == IORESOURCE_MEM) + release_mem_region(gmux_data->iostart, gmux_data->iolen); + else + release_region(gmux_data->iostart, gmux_data->iolen); err_free: kfree(gmux_data); return ret; @@ -772,7 +912,11 @@ static void gmux_remove(struct pnp_dev *pnp) backlight_device_unregister(gmux_data->bdev); - release_region(gmux_data->iostart, gmux_data->iolen); + if (gmux_data->iomem_base) { + iounmap(gmux_data->iomem_base); + release_mem_region(gmux_data->iostart, gmux_data->iolen); + } else + release_region(gmux_data->iostart, gmux_data->iolen); apple_gmux_data = NULL; kfree(gmux_data); diff --git a/include/linux/apple-gmux.h b/include/linux/apple-gmux.h index 147dc1c52e08..272f63f8fd7c 100644 --- a/include/linux/apple-gmux.h +++ b/include/linux/apple-gmux.h @@ -34,11 +34,18 @@ #define GMUX_PORT_READ 0xd0 #define GMUX_PORT_WRITE 0xd4 +#define GMUX_MMIO_PORT_SELECT 0x0e +#define GMUX_MMIO_COMMAND_SEND 0x0f + +#define GMUX_MMIO_READ 0x00 +#define GMUX_MMIO_WRITE 0x40 + #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4) enum apple_gmux_type { APPLE_GMUX_TYPE_PIO, APPLE_GMUX_TYPE_INDEXED, + APPLE_GMUX_TYPE_MMIO, }; #if IS_ENABLED(CONFIG_APPLE_GMUX) @@ -57,6 +64,24 @@ static inline bool apple_gmux_is_indexed(unsigned long iostart) return false; } +static inline bool apple_gmux_is_mmio(unsigned long iostart) +{ + u8 *__iomem iomem_base = ioremap(iostart, 16); + u8 val; + + if (!iomem_base) + return false; + + /* + * If this is 0xff, then gmux must not be present, as the gmux would + * reset it to 0x00, or it would be one of 0x1, 0x4, 0x41, 0x44 if a + * command is currently being processed. + */ + val = ioread8(iomem_base + GMUX_MMIO_COMMAND_SEND); + iounmap(iomem_base); + return (val != 0xff); +} + /** * apple_gmux_detect() - detect if gmux is built into the machine * @@ -93,19 +118,24 @@ static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, enum apple_gmux_ty } res = pnp_get_resource(pnp_dev, IORESOURCE_IO, 0); - if (!res || resource_size(res) < GMUX_MIN_IO_LEN) - goto out; - - /* - * Invalid version information may indicate either that the gmux - * device isn't present or that it's a new one that uses indexed io. - */ - ver_major = inb(res->start + GMUX_PORT_VERSION_MAJOR); - ver_minor = inb(res->start + GMUX_PORT_VERSION_MINOR); - ver_release = inb(res->start + GMUX_PORT_VERSION_RELEASE); - if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { - if (apple_gmux_is_indexed(res->start)) - type = APPLE_GMUX_TYPE_INDEXED; + if (res && resource_size(res) >= GMUX_MIN_IO_LEN) { + /* + * Invalid version information may indicate either that the gmux + * device isn't present or that it's a new one that uses indexed io. + */ + ver_major = inb(res->start + GMUX_PORT_VERSION_MAJOR); + ver_minor = inb(res->start + GMUX_PORT_VERSION_MINOR); + ver_release = inb(res->start + GMUX_PORT_VERSION_RELEASE); + if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { + if (apple_gmux_is_indexed(res->start)) + type = APPLE_GMUX_TYPE_INDEXED; + else + goto out; + } + } else { + res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0); + if (res && apple_gmux_is_mmio(res->start)) + type = APPLE_GMUX_TYPE_MMIO; else goto out; }