| Message ID | 1358352823-6018-1-git-send-email-mika.westerberg@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Wednesday, January 16, 2013 06:13:43 PM Mika Westerberg wrote: > Core System Resources Table (CSRT) is a proprietary ACPI table that > contains resources for certain devices that are not found in the DSDT > table. Typically a shared DMA controller might be found here. > > This patch adds support for this table. We go through all entries in the > table and make platform devices of them. The resources from the table are > passed with the platform device. > > There is one special resource in the table and it is the DMA request line > base and number of request lines. This information might be needed by the > DMA controller driver as it needs to map the ACPI DMA request line number > to the actual request line understood by the hardware. This range is passed > as IORESOURCE_DMA resource. > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> > --- > We got a report that compiling this as 32-bit gives the following warning: > > drivers/acpi/csrt.c:42:5: warning: left shift count >= width of type [enabled by default] > > Since all the CSRT tables we've seen are limited to 32-bit physical > addresses anyway (and the LPSS itself is 32-bit only) we fix this by only > using the low part of the MMIO address for now. > > Sorry about the mess. No biggie. I was about to apply this, but I started to wonder -> > > drivers/acpi/Makefile | 1 + > drivers/acpi/csrt.c | 160 +++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 161 insertions(+) > create mode 100644 drivers/acpi/csrt.c > > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index 4ee2e75..474fcfe 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -38,6 +38,7 @@ acpi-y += processor_core.o > acpi-y += ec.o > acpi-$(CONFIG_ACPI_DOCK) += dock.o > acpi-y += pci_root.o pci_link.o pci_irq.o > +acpi-y += csrt.o > acpi-y += acpi_platform.o > acpi-y += power.o > acpi-y += event.o > diff --git a/drivers/acpi/csrt.c b/drivers/acpi/csrt.c > new file mode 100644 > index 0000000..fe69587 > --- /dev/null > +++ b/drivers/acpi/csrt.c > @@ -0,0 +1,160 @@ > +/* > + * Support for Core System Resources Table (CSRT) > + * > + * Copyright (C) 2013, Intel Corporation > + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> > + * Andy Shevchenko <andriy.shevchenko@linux.intel.com> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#define pr_fmt(fmt) "ACPI: CSRT: " fmt > + > +#include <linux/acpi.h> > +#include <linux/device.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/sizes.h> > + > +ACPI_MODULE_NAME("CSRT"); > + > +static int __init acpi_csrt_parse_shared_info(struct platform_device *pdev, > + const struct acpi_csrt_group *grp) > +{ > + const struct acpi_csrt_shared_info *si; > + struct resource res[3]; > + size_t nres; > + int ret; > + > + memset(res, 0, sizeof(res)); > + nres = 0; > + > + si = (const struct acpi_csrt_shared_info *)&grp[1]; > + /* > + * The peripherals that are listed on CSRT typically support only > + * 32-bit addresses so we only use the low part of MMIO base for > + * now. > + */ > + if (!si->mmio_base_high && si->mmio_base_low) { > + /* > + * There is no size of the memory resource in shared_info > + * so we assume that it is 4k here. > + */ > + res[nres].start = si->mmio_base_low; > + res[nres].end = res[0].start + SZ_4K - 1; > + res[nres++].flags = IORESOURCE_MEM; > + } > + > + if (si->gsi_interrupt) { > + int irq = acpi_register_gsi(NULL, si->gsi_interrupt, > + si->interrupt_mode, > + si->interrupt_polarity); > + res[nres].start = irq; > + res[nres].end = irq; > + res[nres++].flags = IORESOURCE_IRQ; > + } > + > + if (si->base_request_line || si->num_handshake_signals) { > + /* > + * We pass the driver a DMA resource describing the range > + * of request lines the device supports. > + */ > + res[nres].start = si->base_request_line; > + res[nres].end = res[nres].start + si->num_handshake_signals - 1; > + res[nres++].flags = IORESOURCE_DMA; > + } > + > + ret = platform_device_add_resources(pdev, res, nres); > + if (ret) { > + if (si->gsi_interrupt) > + acpi_unregister_gsi(si->gsi_interrupt); > + return ret; > + } > + > + return 0; > +} > + > +static int __init > +acpi_csrt_parse_resource_group(const struct acpi_csrt_group *grp) > +{ > + struct platform_device *pdev; > + char vendor[5], name[16]; > + int ret, i; > + > + vendor[0] = grp->vendor_id; > + vendor[1] = grp->vendor_id >> 8; > + vendor[2] = grp->vendor_id >> 16; > + vendor[3] = grp->vendor_id >> 24; > + vendor[4] = '\0'; > + > + if (grp->shared_info_length != sizeof(struct acpi_csrt_shared_info)) > + return -ENODEV; > + > + snprintf(name, sizeof(name), "%s%04X", vendor, grp->device_id); > + pdev = platform_device_alloc(name, PLATFORM_DEVID_AUTO); > + if (!pdev) > + return -ENOMEM; > + > + /* Add resources based on the shared info */ > + ret = acpi_csrt_parse_shared_info(pdev, grp); > + if (ret) > + goto fail; > + > + ret = platform_device_add(pdev); > + if (ret) > + goto fail; > + > + for (i = 0; i < pdev->num_resources; i++) > + dev_dbg(&pdev->dev, "%pR\n", &pdev->resource[i]); > + > + return 0; > + > +fail: > + platform_device_put(pdev); > + return ret; > +} > + > +/* > + * CSRT or Core System Resources Table is a proprietary ACPI table > + * introduced by Microsoft. This table can contain devices that are not in > + * the system DSDT table. In particular DMA controllers might be described > + * here. > + * > + * We present these devices as normal platform devices that don't have ACPI > + * IDs or handle. The platform device name will be something like > + * <VENDOR><DEVID>.<n>.auto for example: INTL9C06.0.auto. > + */ > +static int __init acpi_csrt_init(void) > +{ > + struct acpi_csrt_group *grp, *end; > + struct acpi_table_csrt *csrt; > + acpi_status status; > + int ret; > + > + status = acpi_get_table(ACPI_SIG_CSRT, 0, > + (struct acpi_table_header **)&csrt); > + if (ACPI_FAILURE(status)) { > + if (status == AE_NOT_FOUND) > + return -ENOENT; > + return -EINVAL; > + } > + > + pr_debug("parsing CSRT table for devices\n"); > + > + grp = (struct acpi_csrt_group *)(csrt + 1); > + end = (struct acpi_csrt_group *)((void *)csrt + csrt->header.length); > + > + while (grp < end) { > + ret = acpi_csrt_parse_resource_group(grp); > + if (ret) > + return ret; > + > + grp = (struct acpi_csrt_group *)((void *)grp + grp->length); > + } > + > + return 0; > +} > +subsys_initcall(acpi_csrt_init); -> Do we really need a separate initcall for that? And what if ACPI is disabled? Perhaps it would be better to call acpi_csrt_init() directly from acpi_init() (or from acpi_scan_init() whichever is more suitable)? Rafael
On Thu, Jan 17, 2013 at 12:27:32AM +0100, Rafael J. Wysocki wrote: > > +static int __init acpi_csrt_init(void) > > +{ > > + struct acpi_csrt_group *grp, *end; > > + struct acpi_table_csrt *csrt; > > + acpi_status status; > > + int ret; > > + > > + status = acpi_get_table(ACPI_SIG_CSRT, 0, > > + (struct acpi_table_header **)&csrt); > > + if (ACPI_FAILURE(status)) { > > + if (status == AE_NOT_FOUND) > > + return -ENOENT; > > + return -EINVAL; > > + } > > + > > + pr_debug("parsing CSRT table for devices\n"); > > + > > + grp = (struct acpi_csrt_group *)(csrt + 1); > > + end = (struct acpi_csrt_group *)((void *)csrt + csrt->header.length); > > + > > + while (grp < end) { > > + ret = acpi_csrt_parse_resource_group(grp); > > + if (ret) > > + return ret; > > + > > + grp = (struct acpi_csrt_group *)((void *)grp + grp->length); > > + } > > + > > + return 0; > > +} > > +subsys_initcall(acpi_csrt_init); > > -> Do we really need a separate initcall for that? And what if ACPI is > disabled? Ah, good point - ACPI can be disabled at runtime as well. > Perhaps it would be better to call acpi_csrt_init() directly from > acpi_init() (or from acpi_scan_init() whichever is more suitable)? Indeed. I'll fix this up and send you a new version soon. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 4ee2e75..474fcfe 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -38,6 +38,7 @@ acpi-y += processor_core.o acpi-y += ec.o acpi-$(CONFIG_ACPI_DOCK) += dock.o acpi-y += pci_root.o pci_link.o pci_irq.o +acpi-y += csrt.o acpi-y += acpi_platform.o acpi-y += power.o acpi-y += event.o diff --git a/drivers/acpi/csrt.c b/drivers/acpi/csrt.c new file mode 100644 index 0000000..fe69587 --- /dev/null +++ b/drivers/acpi/csrt.c @@ -0,0 +1,160 @@ +/* + * Support for Core System Resources Table (CSRT) + * + * Copyright (C) 2013, Intel Corporation + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> + * Andy Shevchenko <andriy.shevchenko@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#define pr_fmt(fmt) "ACPI: CSRT: " fmt + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sizes.h> + +ACPI_MODULE_NAME("CSRT"); + +static int __init acpi_csrt_parse_shared_info(struct platform_device *pdev, + const struct acpi_csrt_group *grp) +{ + const struct acpi_csrt_shared_info *si; + struct resource res[3]; + size_t nres; + int ret; + + memset(res, 0, sizeof(res)); + nres = 0; + + si = (const struct acpi_csrt_shared_info *)&grp[1]; + /* + * The peripherals that are listed on CSRT typically support only + * 32-bit addresses so we only use the low part of MMIO base for + * now. + */ + if (!si->mmio_base_high && si->mmio_base_low) { + /* + * There is no size of the memory resource in shared_info + * so we assume that it is 4k here. + */ + res[nres].start = si->mmio_base_low; + res[nres].end = res[0].start + SZ_4K - 1; + res[nres++].flags = IORESOURCE_MEM; + } + + if (si->gsi_interrupt) { + int irq = acpi_register_gsi(NULL, si->gsi_interrupt, + si->interrupt_mode, + si->interrupt_polarity); + res[nres].start = irq; + res[nres].end = irq; + res[nres++].flags = IORESOURCE_IRQ; + } + + if (si->base_request_line || si->num_handshake_signals) { + /* + * We pass the driver a DMA resource describing the range + * of request lines the device supports. + */ + res[nres].start = si->base_request_line; + res[nres].end = res[nres].start + si->num_handshake_signals - 1; + res[nres++].flags = IORESOURCE_DMA; + } + + ret = platform_device_add_resources(pdev, res, nres); + if (ret) { + if (si->gsi_interrupt) + acpi_unregister_gsi(si->gsi_interrupt); + return ret; + } + + return 0; +} + +static int __init +acpi_csrt_parse_resource_group(const struct acpi_csrt_group *grp) +{ + struct platform_device *pdev; + char vendor[5], name[16]; + int ret, i; + + vendor[0] = grp->vendor_id; + vendor[1] = grp->vendor_id >> 8; + vendor[2] = grp->vendor_id >> 16; + vendor[3] = grp->vendor_id >> 24; + vendor[4] = '\0'; + + if (grp->shared_info_length != sizeof(struct acpi_csrt_shared_info)) + return -ENODEV; + + snprintf(name, sizeof(name), "%s%04X", vendor, grp->device_id); + pdev = platform_device_alloc(name, PLATFORM_DEVID_AUTO); + if (!pdev) + return -ENOMEM; + + /* Add resources based on the shared info */ + ret = acpi_csrt_parse_shared_info(pdev, grp); + if (ret) + goto fail; + + ret = platform_device_add(pdev); + if (ret) + goto fail; + + for (i = 0; i < pdev->num_resources; i++) + dev_dbg(&pdev->dev, "%pR\n", &pdev->resource[i]); + + return 0; + +fail: + platform_device_put(pdev); + return ret; +} + +/* + * CSRT or Core System Resources Table is a proprietary ACPI table + * introduced by Microsoft. This table can contain devices that are not in + * the system DSDT table. In particular DMA controllers might be described + * here. + * + * We present these devices as normal platform devices that don't have ACPI + * IDs or handle. The platform device name will be something like + * <VENDOR><DEVID>.<n>.auto for example: INTL9C06.0.auto. + */ +static int __init acpi_csrt_init(void) +{ + struct acpi_csrt_group *grp, *end; + struct acpi_table_csrt *csrt; + acpi_status status; + int ret; + + status = acpi_get_table(ACPI_SIG_CSRT, 0, + (struct acpi_table_header **)&csrt); + if (ACPI_FAILURE(status)) { + if (status == AE_NOT_FOUND) + return -ENOENT; + return -EINVAL; + } + + pr_debug("parsing CSRT table for devices\n"); + + grp = (struct acpi_csrt_group *)(csrt + 1); + end = (struct acpi_csrt_group *)((void *)csrt + csrt->header.length); + + while (grp < end) { + ret = acpi_csrt_parse_resource_group(grp); + if (ret) + return ret; + + grp = (struct acpi_csrt_group *)((void *)grp + grp->length); + } + + return 0; +} +subsys_initcall(acpi_csrt_init);