mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 11:18:45 +07:00
104a32e85f
In case of error, the function devm_ioremap() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check should
be replaced with NULL test.
Fixes: 6e9b5e7688 ("hwrng: geode - Migrate to managed API")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
120 lines
2.7 KiB
C
120 lines
2.7 KiB
C
/*
|
|
* RNG driver for AMD Geode RNGs
|
|
*
|
|
* Copyright 2005 (c) MontaVista Software, Inc.
|
|
*
|
|
* with the majority of the code coming from:
|
|
*
|
|
* Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
|
|
* (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
|
|
*
|
|
* derived from
|
|
*
|
|
* Hardware driver for the AMD 768 Random Number Generator (RNG)
|
|
* (c) Copyright 2001 Red Hat Inc
|
|
*
|
|
* derived from
|
|
*
|
|
* Hardware driver for Intel i810 Random Number Generator (RNG)
|
|
* Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
|
|
* Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/delay.h>
|
|
#include <linux/hw_random.h>
|
|
#include <linux/io.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pci.h>
|
|
|
|
#define GEODE_RNG_DATA_REG 0x50
|
|
#define GEODE_RNG_STATUS_REG 0x54
|
|
|
|
/*
|
|
* Data for PCI driver interface
|
|
*
|
|
* This data only exists for exporting the supported
|
|
* PCI ids via MODULE_DEVICE_TABLE. We do not actually
|
|
* register a pci_driver, because someone else might one day
|
|
* want to register another driver on the same PCI id.
|
|
*/
|
|
static const struct pci_device_id pci_tbl[] = {
|
|
{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), 0, },
|
|
{ 0, }, /* terminate list */
|
|
};
|
|
MODULE_DEVICE_TABLE(pci, pci_tbl);
|
|
|
|
|
|
static int geode_rng_data_read(struct hwrng *rng, u32 *data)
|
|
{
|
|
void __iomem *mem = (void __iomem *)rng->priv;
|
|
|
|
*data = readl(mem + GEODE_RNG_DATA_REG);
|
|
|
|
return 4;
|
|
}
|
|
|
|
static int geode_rng_data_present(struct hwrng *rng, int wait)
|
|
{
|
|
void __iomem *mem = (void __iomem *)rng->priv;
|
|
int data, i;
|
|
|
|
for (i = 0; i < 20; i++) {
|
|
data = !!(readl(mem + GEODE_RNG_STATUS_REG));
|
|
if (data || !wait)
|
|
break;
|
|
udelay(10);
|
|
}
|
|
return data;
|
|
}
|
|
|
|
|
|
static struct hwrng geode_rng = {
|
|
.name = "geode",
|
|
.data_present = geode_rng_data_present,
|
|
.data_read = geode_rng_data_read,
|
|
};
|
|
|
|
|
|
static int __init mod_init(void)
|
|
{
|
|
struct pci_dev *pdev = NULL;
|
|
const struct pci_device_id *ent;
|
|
void __iomem *mem;
|
|
unsigned long rng_base;
|
|
|
|
for_each_pci_dev(pdev) {
|
|
ent = pci_match_id(pci_tbl, pdev);
|
|
if (ent) {
|
|
rng_base = pci_resource_start(pdev, 0);
|
|
if (rng_base == 0)
|
|
return -ENODEV;
|
|
|
|
mem = devm_ioremap(&pdev->dev, rng_base, 0x58);
|
|
if (!mem)
|
|
return -ENOMEM;
|
|
geode_rng.priv = (unsigned long)mem;
|
|
|
|
pr_info("AMD Geode RNG detected\n");
|
|
return devm_hwrng_register(&pdev->dev, &geode_rng);
|
|
}
|
|
}
|
|
|
|
/* Device not found. */
|
|
return -ENODEV;
|
|
}
|
|
|
|
static void __exit mod_exit(void)
|
|
{
|
|
}
|
|
|
|
module_init(mod_init);
|
|
module_exit(mod_exit);
|
|
|
|
MODULE_DESCRIPTION("H/W RNG driver for AMD Geode LX CPUs");
|
|
MODULE_LICENSE("GPL");
|