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-rw-r--r--drivers/pnp/system.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/drivers/pnp/system.c b/drivers/pnp/system.c
new file mode 100644
index 0000000000..835113b2cb
--- /dev/null
+++ b/drivers/pnp/system.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * system.c - a driver for reserving pnp system resources
+ *
+ * Some code is based on pnpbios_core.c
+ * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
+ * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ */
+
+#include <linux/pnp.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+
+static const struct pnp_device_id pnp_dev_table[] = {
+ /* General ID for reserving resources */
+ {"PNP0c02", 0},
+ /* memory controller */
+ {"PNP0c01", 0},
+ {"", 0}
+};
+
+static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
+{
+ char *regionid;
+ const char *pnpid = dev_name(&dev->dev);
+ resource_size_t start = r->start, end = r->end;
+ struct resource *res;
+
+ regionid = kmalloc(16, GFP_KERNEL);
+ if (!regionid)
+ return;
+
+ snprintf(regionid, 16, "pnp %s", pnpid);
+ if (port)
+ res = request_region(start, end - start + 1, regionid);
+ else
+ res = request_mem_region(start, end - start + 1, regionid);
+ if (res)
+ res->flags &= ~IORESOURCE_BUSY;
+ else
+ kfree(regionid);
+
+ /*
+ * Failures at this point are usually harmless. pci quirks for
+ * example do reserve stuff they know about too, so we may well
+ * have double reservations.
+ */
+ dev_info(&dev->dev, "%pR %s reserved\n", r,
+ res ? "has been" : "could not be");
+}
+
+static void reserve_resources_of_dev(struct pnp_dev *dev)
+{
+ struct resource *res;
+ int i;
+
+ for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
+ if (res->flags & IORESOURCE_DISABLED)
+ continue;
+ if (res->start == 0)
+ continue; /* disabled */
+ if (res->start < 0x100)
+ /*
+ * Below 0x100 is only standard PC hardware
+ * (pics, kbd, timer, dma, ...)
+ * We should not get resource conflicts there,
+ * and the kernel reserves these anyway
+ * (see arch/i386/kernel/setup.c).
+ * So, do nothing
+ */
+ continue;
+ if (res->end < res->start)
+ continue; /* invalid */
+
+ reserve_range(dev, res, 1);
+ }
+
+ for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
+ if (res->flags & IORESOURCE_DISABLED)
+ continue;
+
+ reserve_range(dev, res, 0);
+ }
+}
+
+static int system_pnp_probe(struct pnp_dev *dev,
+ const struct pnp_device_id *dev_id)
+{
+ reserve_resources_of_dev(dev);
+ return 0;
+}
+
+static struct pnp_driver system_pnp_driver = {
+ .name = "system",
+ .id_table = pnp_dev_table,
+ .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
+ .probe = system_pnp_probe,
+};
+
+static int __init pnp_system_init(void)
+{
+ return pnp_register_driver(&system_pnp_driver);
+}
+
+/*
+ * Reserve motherboard resources after PCI claim BARs,
+ * but before PCI assign resources for uninitialized PCI devices
+ */
+fs_initcall(pnp_system_init);