Re: ACPI + Floppy detection problem in 2.6.8.1-mm4

Bjorn Helgaas
2004-08-25T20:32:46Z

> > inserting floppy driver for 2.6.8.1-mm4
> > acpi_floppy_resource: 6 ioports at 0x3f0
> > acpi_floppy_resource: 1 ioports at 0x3f7
> > floppy: controller ACPI FDC0 at I/O 0x3f0-0x3f5, 0x3f7-0x3f7 irq 6 dma channel 2
> > Floppy drive(s): fd0 is 1.44M
> > floppy0: no floppy controllers found

Aric and Petr, can you give this patch a try? It's a replacement for the
one currently in 2.6.8.1-mm4. I adopted Petr's strategy of just clearing
the low three bits of the first I/O port region, and also his module
unload fixes.

I also added a couple validity checks (for firmware that doesn't
report 0x3f7 or reports 0x3f0 or 0x3f6), and made them ignore the
device altogether if "acpi=strict". Any comments on that, Len?

Add ACPI-based floppy controller enumeration.

This can be disabled with "floppy=no_acpi", which should only be
required if your BIOS supplies incorrect ACPI _CRS information about
I/O ports, IRQs, or DMA channels.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>

===== Documentation/floppy.txt 1.1 vs edited =====
--- 1.1/Documentation/floppy.txt 2002-02-05 10:40:38 -07:00
+++ edited/Documentation/floppy.txt 2004-08-18 15:41:37 -06:00
@@ -187,6 +187,11 @@
It's been recommended that take about 1/4 of the default speed
in some more extreme cases."

+ floppy=no_acpi
+ Don't enumerate floppy controllers using ACPI namespace.
+ You may need this if your ACPI is buggy and reports incorrect
+ I/O port, IRQ, or DMA information.
+

Supporting utilities and additional documentation:
===== drivers/block/floppy.c 1.103 vs edited =====
--- 1.103/drivers/block/floppy.c 2004-08-02 02:00:45 -06:00
+++ edited/drivers/block/floppy.c 2004-08-25 13:43:33 -06:00
@@ -181,6 +181,13 @@
#include <linux/device.h>
#include <linux/buffer_head.h> /* for invalidate_buffers() */

+#ifdef CONFIG_ACPI_BUS
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+
+static int no_acpi_floppy;
+#endif
+
/*
* PS/2 floppies have much slower step rates than regular floppies.
* It's been recommended that take about 1/4 of the default speed
@@ -4150,6 +4157,9 @@
{"slow", NULL, &slow_floppy, 1, 0},
{"unexpected_interrupts", NULL, &print_unex, 1, 0},
{"no_unexpected_interrupts", NULL, &print_unex, 0, 0},
+#ifdef CONFIG_ACPI_BUS
+ {"no_acpi", NULL, &no_acpi_floppy, 1, 0},
+#endif
{"L40SX", NULL, &print_unex, 0, 0}

EXTRA_FLOPPY_PARAMS
@@ -4222,11 +4232,192 @@
return get_disk(disks[drive]);
}

+#ifdef CONFIG_ACPI_BUS
+static int acpi_floppy_registered;
+static int acpi_floppies;
+
+struct region {
+ unsigned int base;
+ unsigned int size;
+};
+
+struct floppy_resources {
+ unsigned int nr_io_regions;
+ struct region io_region[2];
+ unsigned int irq;
+ unsigned int dma_channel;
+};
+
+static acpi_status acpi_floppy_resource(struct acpi_resource *res, void *data)
+{
+ struct floppy_resources *fd = (struct floppy_resources *) data;
+ struct acpi_resource_io *io;
+ struct acpi_resource_irq *irq;
+ struct acpi_resource_ext_irq *ext_irq;
+ struct acpi_resource_dma *dma;
+ int n;
+
+ if (res->id == ACPI_RSTYPE_IO) {
+ io = &res->data.io;
+ if (io->range_length) {
+ n = fd->nr_io_regions;
+ if (n < 2) {
+ fd->io_region[n].base = io->min_base_address;
+ fd->io_region[n].size = io->range_length;
+ fd->nr_io_regions++;
+ } else {
+ printk(KERN_WARNING "%s: ignoring I/O port region 0x%x-0x%x\n",
+ DEVICE_NAME, io->min_base_address,
+ io->min_base_address + io->range_length - 1);
+ }
+ }
+ } else if (res->id == ACPI_RSTYPE_IRQ) {
+ irq = &res->data.irq;
+ if (irq->number_of_interrupts > 0)
+ fd->irq = acpi_register_gsi(irq->interrupts[0],
+ irq->edge_level, irq->active_high_low);
+ } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
+ ext_irq = &res->data.extended_irq;
+ if (ext_irq->number_of_interrupts > 0)
+ fd->irq = acpi_register_gsi(ext_irq->interrupts[0],
+ ext_irq->edge_level, ext_irq->active_high_low);
+ } else if (res->id == ACPI_RSTYPE_DMA) {
+ dma = &res->data.dma;
+ if (dma->number_of_channels > 0)
+ fd->dma_channel = dma->channels[0];
+ }
+ return AE_OK;
+}
+
+static int acpi_floppy_add(struct acpi_device *device)
+{
+ struct floppy_resources fd;
+ acpi_status status;
+ unsigned int base, dcr, ide;
+
+ memset(&fd, 0, sizeof(fd));
+ status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
+ acpi_floppy_resource, &fd);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ printk("%s: controller ACPI %s at I/O 0x%x-0x%x",
+ DEVICE_NAME, device->pnp.bus_id, fd.io_region[0].base,
+ fd.io_region[0].base + fd.io_region[0].size - 1);
+ if (fd.nr_io_regions > 1) {
+ if (fd.io_region[1].size == 1)
+ printk(", 0x%x", fd.io_region[1].base);
+ else
+ printk(", 0x%x-0x%x", fd.io_region[1].base,
+ fd.io_region[1].base + fd.io_region[1].size - 1);
+ }
+ printk(" irq %d dma channel %d\n", fd.irq, fd.dma_channel);
+
+ /*
+ * The most correct resource description is probably of the form
+ * 0x3f2-0x3f5, 0x3f7
+ * Those are the only ports this driver actually uses.
+ *
+ * 0x3f0 and 0x3f1 were apparently used on PS/2 systems (though
+ * this driver doesn't touch them), and 0x3f6 is used by IDE.
+ * Some BIOS's erroneously include those ports, or omit 0x3f7,
+ * so we should also be able to handle the following:
+ * 0x3f0-0x3f5
+ * 0x3f0-0x3f5, 0x3f7
+ * 0x3f0-0x3f7
+ * 0x3f2-0x3f7
+ */
+ base = fd.io_region[0].base & ~0x7;
+ ide = base + 6;
+ dcr = base + 7;
+
+#define contains(region, port) ((region).base <= (port) && \
+ (port) < (region).base + (region).size)
+
+ if (!(contains(fd.io_region[0], dcr) || contains(fd.io_region[1], dcr))) {
+ printk(KERN_WARNING "%s: %s _CRS doesn't include FD_DCR; assuming 0x%x\n",
+ DEVICE_NAME, device->pnp.bus_id, dcr);
+ if (acpi_strict)
+ return -ENODEV;
+ }
+
+ if (contains(fd.io_region[0], base)) {
+ printk(KERN_WARNING "%s: %s _CRS erroneously includes 0x%x\n",
+ DEVICE_NAME, device->pnp.bus_id, base);
+ if (acpi_strict)
+ return -ENODEV;
+ }
+
+ if (contains(fd.io_region[0], ide)) {
+ printk(KERN_WARNING "%s: %s _CRS erroneously includes 0x%x\n",
+ DEVICE_NAME, device->pnp.bus_id, ide);
+ if (acpi_strict)
+ return -ENODEV;
+ }
+
+#undef contains
+
+ if (acpi_floppies == 0) {
+ FDC1 = base;
+ FLOPPY_IRQ = fd.irq;
+ FLOPPY_DMA = fd.dma_channel;
+ } else if (acpi_floppies == 1) {
+ FDC2 = base;
+ if (fd.irq != FLOPPY_IRQ || fd.dma_channel != FLOPPY_DMA)
+ printk(KERN_WARNING "%s: different IRQ/DMA info for %s; may not work\n",
+ DEVICE_NAME, device->pnp.bus_id);
+ } else {
+ printk(KERN_ERR "%s: only 2 controllers supported; %s ignored\n",
+ DEVICE_NAME, device->pnp.bus_id);
+ return -ENODEV;
+ }
+
+ acpi_floppies++;
+ return 0;
+}
+
+static struct acpi_driver acpi_floppy_driver = {
+ .name = "floppy",
+ .ids = "PNP0700",
+ .ops = {
+ .add = acpi_floppy_add,
+ },
+};
+
+static int acpi_floppy_init(void)
+{
+ int err;
+
+ if (no_acpi_floppy)
+ return -ENODEV;
+ err = acpi_bus_register_driver(&acpi_floppy_driver);
+ if (err >= 0)
+ acpi_floppy_registered = 1;
+ return err;
+}
+
+static void acpi_floppy_exit(void)
+{
+ if (acpi_floppy_registered) {
+ acpi_bus_unregister_driver(&acpi_floppy_driver);
+ acpi_floppy_registered = 0;
+ }
+}
+#else
+static int acpi_floppy_init(void) { return -ENODEV; }
+static void acpi_floppy_stop(void) { }
+#endif
+
int __init floppy_init(void)
{
int i, unit, drive;
int err, dr;

+ if (acpi_floppy_init() == 0) {
+ err = -ENODEV;
+ goto out_put_acpi;
+ }
+
raw_cmd = NULL;

for (dr = 0; dr < N_DRIVE; dr++) {
@@ -4404,6 +4595,8 @@
del_timer(&motor_off_timer[dr]);
put_disk(disks[dr]);
}
+out_put_acpi:
+ acpi_floppy_exit();
return err;
}

@@ -4619,6 +4812,8 @@

/* eject disk, if any */
fd_eject(0);
+
+ acpi_floppy_exit();

wait_for_completion(&device_release);
}