]> git.karo-electronics.de Git - linux-beck.git/commitdiff
FMC: add a software carrier driver
authorAlessandro Rubini <rubini@gnudd.com>
Tue, 18 Jun 2013 21:47:35 +0000 (23:47 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 18 Jun 2013 22:41:04 +0000 (15:41 -0700)
This fake carrier is designed to help FMC users understand how a
carrier driver works, and to experiment the behaviour with EEPROM
reprogramming (with a mezzanine driver commited later). This carrier
can register up to 4 (fake) mezzanines.

We have real carriers (both on PCI-E and VME), but they are bigger
things and are not part of this submission.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Juan David Gonzalez Cobas <dcobas@cern.ch>
Acked-by: Emilio G. Cota <cota@braap.org>
Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Documentation/fmc/00-INDEX
Documentation/fmc/fmc-fakedev.txt [new file with mode: 0644]
drivers/fmc/Kconfig
drivers/fmc/Makefile
drivers/fmc/fmc-fakedev.c [new file with mode: 0644]

index 71304b7fc4919c4b4573c545e7b26e98b4c03a8f..34df5cfc0c41215193be613a850ac19a710026ce 100644 (file)
@@ -24,3 +24,6 @@ mezzanine.txt
 
 identifiers.txt
        - how identification and matching works
+
+fmc-fakedev.txt
+       - about drivers/fmc/fmc-fakedev.ko
diff --git a/Documentation/fmc/fmc-fakedev.txt b/Documentation/fmc/fmc-fakedev.txt
new file mode 100644 (file)
index 0000000..e85b74a
--- /dev/null
@@ -0,0 +1,36 @@
+fmc-fakedev
+===========
+
+This package includes a software-only device, called fmc-fakedev, which
+is able to register up to 4 mezzanines (by default it registers one).
+Unlike the SPEC driver, which creates an FMC device for each PCI cards
+it manages, this module creates a single instance of its set of
+mezzanines.
+
+It is meant as the simplest possible example of how a driver should be
+written, and it includes a fake EEPROM image (built using the tools
+described in *note FMC Identification::),, which by default is
+replicated for each fake mezzanine.
+
+You can also use this device to verify the match algorithms, by asking
+it to test your own EEPROM image. You can provide the image by means of
+the eeprom= module parameter: the new EEPROM image is loaded, as usual,
+by means of the firmware loader.  This example shows the defaults and a
+custom EEPROM image:
+
+     spusa.root# insmod fmc-fakedev.ko
+     [   99.971247]  fake-fmc-carrier: mezzanine 0
+     [   99.975393]       Manufacturer: fake-vendor
+     [   99.979624]       Product name: fake-design-for-testing
+     spusa.root# rmmod fmc-fakedev
+     spusa.root# insmod fmc-fakedev.ko eeprom=fdelay-eeprom.bin
+     [  121.447464]  fake-fmc-carrier: Mezzanine 0: eeprom "fdelay-eeprom.bin"
+     [  121.462725]  fake-fmc-carrier: mezzanine 0
+     [  121.466858]       Manufacturer: CERN
+     [  121.470477]       Product name: FmcDelay1ns4cha
+     spusa.root# rmmod fmc-fakedev
+
+After loading the device, you can use the write_ee method do modify its
+own internal fake EEPROM: whenever the image is overwritten starting at
+offset 0, the module will unregister and register again the FMC device.
+This is shown in fmc-write-eeprom.txt
index e28790267c6962f243890e8dce4b16dadd2c8bb4..505e96b02a939ce86cdd7c3ed3b88b103ec43f0d 100644 (file)
@@ -15,3 +15,14 @@ menuconfig FMC
          The framework was born outside of the kernel and at this time
          the off-tree code base is more complete.  Code and documentation
          is at git://ohwr.org/fmc-projects/fmc-bus.git .
+
+if FMC
+
+config FMC_FAKEDEV
+       tristate "FMC fake device (software testing)"
+       help
+         This is a fake carrier, bringing a default EEPROM content
+         that can be rewritten at run time and usef for matching
+         mezzanines.
+
+endif # FMC
index df9893972a628d17e371c13a5402596b246140af..9832b79976b151ffeafa3b687653f27b74125cfa 100644 (file)
@@ -6,3 +6,5 @@ fmc-y += fmc-match.o
 fmc-y += fmc-sdb.o
 fmc-y += fru-parse.o
 fmc-y += fmc-dump.o
+
+obj-$(CONFIG_FMC_FAKEDEV) += fmc-fakedev.o
diff --git a/drivers/fmc/fmc-fakedev.c b/drivers/fmc/fmc-fakedev.c
new file mode 100644 (file)
index 0000000..bec94ac
--- /dev/null
@@ -0,0 +1,355 @@
+/*
+ * Copyright (C) 2012 CERN (www.cern.ch)
+ * Author: Alessandro Rubini <rubini@gnudd.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * The software is provided "as is"; the copyright holders disclaim
+ * all warranties and liabilities, to the extent permitted by
+ * applicable law.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/firmware.h>
+#include <linux/workqueue.h>
+#include <linux/err.h>
+#include <linux/fmc.h>
+
+#define FF_EEPROM_SIZE         8192    /* The standard eeprom size */
+#define FF_MAX_MEZZANINES      4       /* Fakes a multi-mezzanine carrier */
+
+/* The user can pass up to 4 names of eeprom images to load */
+static char *ff_eeprom[FF_MAX_MEZZANINES];
+static int ff_nr_eeprom;
+module_param_array_named(eeprom, ff_eeprom, charp, &ff_nr_eeprom, 0444);
+
+/* The user can ask for a multi-mezzanine carrier, with the default eeprom */
+static int ff_nr_dev = 1;
+module_param_named(ndev, ff_nr_dev, int, 0444);
+
+
+/* Lazily, don't support the "standard" module parameters */
+
+/*
+ * Eeprom built from these commands:
+
+       ../fru-generator -v fake-vendor -n fake-design-for-testing \
+               -s 01234 -p none > IPMI-FRU
+
+       gensdbfs . ../fake-eeprom.bin
+*/
+static char ff_eeimg[FF_MAX_MEZZANINES][FF_EEPROM_SIZE] = {
+       {
+       0x01, 0x00, 0x00, 0x01, 0x00, 0x0c, 0x00, 0xf2, 0x01, 0x0b, 0x00, 0xb2,
+       0x86, 0x87, 0xcb, 0x66, 0x61, 0x6b, 0x65, 0x2d, 0x76, 0x65, 0x6e, 0x64,
+       0x6f, 0x72, 0xd7, 0x66, 0x61, 0x6b, 0x65, 0x2d, 0x64, 0x65, 0x73, 0x69,
+       0x67, 0x6e, 0x2d, 0x66, 0x6f, 0x72, 0x2d, 0x74, 0x65, 0x73, 0x74, 0x69,
+       0x6e, 0x67, 0xc5, 0x30, 0x31, 0x32, 0x33, 0x34, 0xc4, 0x6e, 0x6f, 0x6e,
+       0x65, 0xda, 0x32, 0x30, 0x31, 0x32, 0x2d, 0x31, 0x31, 0x2d, 0x31, 0x39,
+       0x20, 0x32, 0x32, 0x3a, 0x34, 0x32, 0x3a, 0x33, 0x30, 0x2e, 0x30, 0x37,
+       0x34, 0x30, 0x35, 0x35, 0xc1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x87,
+       0x02, 0x02, 0x0d, 0xf7, 0xf8, 0x02, 0xb0, 0x04, 0x74, 0x04, 0xec, 0x04,
+       0x00, 0x00, 0x00, 0x00, 0xe8, 0x03, 0x02, 0x02, 0x0d, 0x5c, 0x93, 0x01,
+       0x4a, 0x01, 0x39, 0x01, 0x5a, 0x01, 0x00, 0x00, 0x00, 0x00, 0xb8, 0x0b,
+       0x02, 0x02, 0x0d, 0x63, 0x8c, 0x00, 0xfa, 0x00, 0xed, 0x00, 0x06, 0x01,
+       0x00, 0x00, 0x00, 0x00, 0xa0, 0x0f, 0x01, 0x02, 0x0d, 0xfb, 0xf5, 0x05,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x01, 0x02, 0x0d, 0xfc, 0xf4, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x0d, 0xfd, 0xf3, 0x03,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0xfa, 0x82, 0x0b, 0xea, 0x8f, 0xa2, 0x12, 0x00, 0x00, 0x1e, 0x44, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x53, 0x44, 0x42, 0x2d, 0x00, 0x03, 0x01, 0x01,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x01, 0xc4, 0x46, 0x69, 0x6c, 0x65, 0x44, 0x61, 0x74, 0x61,
+       0x2e, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
+       0x2e, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+       0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xc0,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xc4, 0x46, 0x69, 0x6c, 0x65,
+       0x44, 0x61, 0x74, 0x61, 0x6e, 0x61, 0x6d, 0x65, 0x00, 0x00, 0x00, 0x01,
+       0x00, 0x00, 0x00, 0x00, 0x6e, 0x61, 0x6d, 0x65, 0x20, 0x20, 0x20, 0x20,
+       0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x01,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xdf,
+       0x46, 0x69, 0x6c, 0x65, 0x44, 0x61, 0x74, 0x61, 0x49, 0x50, 0x4d, 0x49,
+       0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x49, 0x50, 0x4d, 0x49,
+       0x2d, 0x46, 0x52, 0x55, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+       0x20, 0x20, 0x20, 0x01, 0x66, 0x61, 0x6b, 0x65, 0x0a,
+       },
+};
+
+struct ff_dev {
+       struct fmc_device *fmc[FF_MAX_MEZZANINES];
+       struct device dev;
+};
+
+static struct ff_dev *ff_current_dev; /* We have 1 carrier, 1 slot */
+
+static int ff_reprogram(struct fmc_device *fmc, struct fmc_driver *drv,
+                         char *gw)
+{
+       const struct firmware *fw;
+       int ret;
+
+       if (!gw) {
+               /* program golden: success */
+               fmc->flags &= ~FMC_DEVICE_HAS_CUSTOM;
+               fmc->flags |= FMC_DEVICE_HAS_GOLDEN;
+               return 0;
+       }
+
+       dev_info(&fmc->dev, "reprogramming with %s\n", gw);
+       ret = request_firmware(&fw, gw, &fmc->dev);
+       if (ret < 0) {
+               dev_warn(&fmc->dev, "request firmware \"%s\": error %i\n",
+                        gw, ret);
+               goto out;
+       }
+       fmc->flags &= ~FMC_DEVICE_HAS_GOLDEN;
+       fmc->flags |= FMC_DEVICE_HAS_CUSTOM;
+
+out:
+       release_firmware(fw);
+       return ret;
+}
+
+static int ff_irq_request(struct fmc_device *fmc, irq_handler_t handler,
+                           char *name, int flags)
+{
+       return -EOPNOTSUPP;
+}
+
+/* FIXME: should also have some fake FMC GPIO mapping */
+
+
+/*
+ * This work function is called when we changed the eeprom. It removes the
+ * current fmc device and registers a new one, with different identifiers.
+ */
+static struct ff_dev *ff_dev_create(void); /* defined later */
+
+static void ff_work_fn(struct work_struct *work)
+{
+       struct ff_dev *ff = ff_current_dev;
+       int ret;
+
+       fmc_device_unregister_n(ff->fmc, ff_nr_dev);
+       device_unregister(&ff->dev);
+       ff_current_dev = NULL;
+
+       ff = ff_dev_create();
+       if (IS_ERR(ff)) {
+               pr_warning("%s: can't re-create FMC devices\n", __func__);
+               return;
+       }
+       ret = fmc_device_register_n(ff->fmc, ff_nr_dev);
+       if (ret < 0) {
+               dev_warn(&ff->dev, "can't re-register FMC devices\n");
+               device_unregister(&ff->dev);
+               return;
+       }
+
+       ff_current_dev = ff;
+}
+
+static DECLARE_DELAYED_WORK(ff_work, ff_work_fn);
+
+
+/* low-level i2c */
+static int ff_eeprom_read(struct fmc_device *fmc, uint32_t offset,
+               void *buf, size_t size)
+{
+       if (offset > FF_EEPROM_SIZE)
+               return -EINVAL;
+       if (offset + size > FF_EEPROM_SIZE)
+               size = FF_EEPROM_SIZE - offset;
+       memcpy(buf, fmc->eeprom + offset, size);
+       return size;
+}
+
+static int ff_eeprom_write(struct fmc_device *fmc, uint32_t offset,
+                   const void *buf, size_t size)
+{
+       if (offset > FF_EEPROM_SIZE)
+               return -EINVAL;
+       if (offset + size > FF_EEPROM_SIZE)
+               size = FF_EEPROM_SIZE - offset;
+       dev_info(&fmc->dev, "write_eeprom: offset %i, size %zi\n",
+                (int)offset, size);
+       memcpy(fmc->eeprom + offset, buf, size);
+       schedule_delayed_work(&ff_work, HZ * 2); /* remove, replug, in 2s */
+       return size;
+}
+
+/* i2c operations for fmc */
+static int ff_read_ee(struct fmc_device *fmc, int pos, void *data, int len)
+{
+       if (!(fmc->flags & FMC_DEVICE_HAS_GOLDEN))
+               return -EOPNOTSUPP;
+       return ff_eeprom_read(fmc, pos, data, len);
+}
+
+static int ff_write_ee(struct fmc_device *fmc, int pos,
+                        const void *data, int len)
+{
+       if (!(fmc->flags & FMC_DEVICE_HAS_GOLDEN))
+               return -EOPNOTSUPP;
+       return ff_eeprom_write(fmc, pos, data, len);
+}
+
+/* readl and writel do not do anything. Don't waste RAM with "base" */
+static uint32_t ff_readl(struct fmc_device *fmc, int offset)
+{
+       return 0;
+}
+
+static void ff_writel(struct fmc_device *fmc, uint32_t value, int offset)
+{
+       return;
+}
+
+/* validate is useful so fmc-write-eeprom will not reprogram every 2 seconds */
+static int ff_validate(struct fmc_device *fmc, struct fmc_driver *drv)
+{
+       int i;
+
+       if (!drv->busid_n)
+               return 0; /* everyhing is valid */
+       for (i = 0; i < drv->busid_n; i++)
+               if (drv->busid_val[i] == fmc->device_id)
+                       return i;
+       return -ENOENT;
+}
+
+
+
+static struct fmc_operations ff_fmc_operations = {
+       .readl =                ff_readl,
+       .writel =               ff_writel,
+       .reprogram =            ff_reprogram,
+       .irq_request =          ff_irq_request,
+       .read_ee =              ff_read_ee,
+       .write_ee =             ff_write_ee,
+       .validate =             ff_validate,
+};
+
+/* This device is kmalloced: release it */
+static void ff_dev_release(struct device *dev)
+{
+       struct ff_dev *ff = container_of(dev, struct ff_dev, dev);
+       kfree(ff);
+}
+
+static struct fmc_device ff_template_fmc = {
+       .version = FMC_VERSION,
+       .owner = THIS_MODULE,
+       .carrier_name = "fake-fmc-carrier",
+       .device_id = 0xf001, /* fool */
+       .eeprom_len = sizeof(ff_eeimg[0]),
+       .memlen = 0x1000, /* 4k, to show something */
+       .op = &ff_fmc_operations,
+       .hwdev = NULL, /* filled at creation time */
+       .flags = FMC_DEVICE_HAS_GOLDEN,
+};
+
+static struct ff_dev *ff_dev_create(void)
+{
+       struct ff_dev *ff;
+       struct fmc_device *fmc;
+       int i, ret;
+
+       ff = kzalloc(sizeof(*ff), GFP_KERNEL);
+       if (!ff)
+               return ERR_PTR(-ENOMEM);
+       dev_set_name(&ff->dev, "fake-fmc-carrier");
+       ff->dev.release = ff_dev_release;
+
+       ret = device_register(&ff->dev);
+       if (ret < 0) {
+               put_device(&ff->dev);
+               return ERR_PTR(ret);
+       }
+
+       /* Create fmc structures that refer to this new "hw" device */
+       for (i = 0; i < ff_nr_dev; i++) {
+               fmc = kmemdup(&ff_template_fmc, sizeof(ff_template_fmc),
+                             GFP_KERNEL);
+               fmc->hwdev = &ff->dev;
+               fmc->carrier_data = ff;
+               fmc->nr_slots = ff_nr_dev;
+               /* the following fields are different for each slot */
+               fmc->eeprom = ff_eeimg[i];
+               fmc->eeprom_addr = 0x50 + 2 * i;
+               fmc->slot_id = i;
+               ff->fmc[i] = fmc;
+               /* increment the identifier, each must be different */
+               ff_template_fmc.device_id++;
+       }
+       return ff;
+}
+
+/* init and exit */
+static int ff_init(void)
+{
+       struct ff_dev *ff;
+       const struct firmware *fw;
+       int i, len, ret = 0;
+
+       /* Replicate the default eeprom for the max number of mezzanines */
+       for (i = 1; i < FF_MAX_MEZZANINES; i++)
+               memcpy(ff_eeimg[i], ff_eeimg[0], sizeof(ff_eeimg[0]));
+
+       if (ff_nr_eeprom > ff_nr_dev)
+               ff_nr_dev = ff_nr_eeprom;
+
+       ff = ff_dev_create();
+       if (IS_ERR(ff))
+               return PTR_ERR(ff);
+
+       /* If the user passed "eeprom=" as a parameter, fetch them */
+       for (i = 0; i < ff_nr_eeprom; i++) {
+               if (!strlen(ff_eeprom[i]))
+                       continue;
+               ret = request_firmware(&fw, ff_eeprom[i], &ff->dev);
+               if (ret < 0) {
+                       dev_err(&ff->dev, "Mezzanine %i: can't load \"%s\" "
+                               "(error %i)\n", i, ff_eeprom[i], -ret);
+               } else {
+                       len = min_t(size_t, fw->size, (size_t)FF_EEPROM_SIZE);
+                       memcpy(ff_eeimg[i], fw->data, len);
+                       release_firmware(fw);
+                       dev_info(&ff->dev, "Mezzanine %i: eeprom \"%s\"\n", i,
+                               ff_eeprom[i]);
+               }
+       }
+
+       ret = fmc_device_register_n(ff->fmc, ff_nr_dev);
+       if (ret) {
+               device_unregister(&ff->dev);
+               return ret;
+       }
+       ff_current_dev = ff;
+       return ret;
+}
+
+static void ff_exit(void)
+{
+       if (ff_current_dev) {
+               fmc_device_unregister_n(ff_current_dev->fmc, ff_nr_dev);
+               device_unregister(&ff_current_dev->dev);
+       }
+       cancel_delayed_work_sync(&ff_work);
+}
+
+module_init(ff_init);
+module_exit(ff_exit);
+
+MODULE_LICENSE("Dual BSD/GPL");