diff options
author | David Daney <ddaney@caviumnetworks.com> | 2009-08-20 14:10:23 -0700 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2009-09-17 20:07:51 +0200 |
commit | f7557dc8215a2e7eb22da583d03e1aef72c58b3c (patch) | |
tree | 8442ce8e8e9d26fed39af469c4eef3f335adf6fe /drivers/char/hw_random/octeon-rng.c | |
parent | e26449153c386904d2801d6348d66d00e5ba2211 (diff) |
MIPS: hw_random: Add hardware RNG for Octeon SOCs.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'drivers/char/hw_random/octeon-rng.c')
-rw-r--r-- | drivers/char/hw_random/octeon-rng.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/char/hw_random/octeon-rng.c b/drivers/char/hw_random/octeon-rng.c new file mode 100644 index 00000000000..54b0d9ba65c --- /dev/null +++ b/drivers/char/hw_random/octeon-rng.c @@ -0,0 +1,147 @@ +/* + * Hardware Random Number Generator support for Cavium Networks + * Octeon processor family. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2009 Cavium Networks + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/device.h> +#include <linux/hw_random.h> +#include <linux/io.h> + +#include <asm/octeon/octeon.h> +#include <asm/octeon/cvmx-rnm-defs.h> + +struct octeon_rng { + struct hwrng ops; + void __iomem *control_status; + void __iomem *result; +}; + +static int octeon_rng_init(struct hwrng *rng) +{ + union cvmx_rnm_ctl_status ctl; + struct octeon_rng *p = container_of(rng, struct octeon_rng, ops); + + ctl.u64 = 0; + ctl.s.ent_en = 1; /* Enable the entropy source. */ + ctl.s.rng_en = 1; /* Enable the RNG hardware. */ + cvmx_write_csr((u64)p->control_status, ctl.u64); + return 0; +} + +static void octeon_rng_cleanup(struct hwrng *rng) +{ + union cvmx_rnm_ctl_status ctl; + struct octeon_rng *p = container_of(rng, struct octeon_rng, ops); + + ctl.u64 = 0; + /* Disable everything. */ + cvmx_write_csr((u64)p->control_status, ctl.u64); +} + +static int octeon_rng_data_read(struct hwrng *rng, u32 *data) +{ + struct octeon_rng *p = container_of(rng, struct octeon_rng, ops); + + *data = cvmx_read64_uint32((u64)p->result); + return sizeof(u32); +} + +static int __devinit octeon_rng_probe(struct platform_device *pdev) +{ + struct resource *res_ports; + struct resource *res_result; + struct octeon_rng *rng; + int ret; + struct hwrng ops = { + .name = "octeon", + .init = octeon_rng_init, + .cleanup = octeon_rng_cleanup, + .data_read = octeon_rng_data_read + }; + + rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL); + if (!rng) + return -ENOMEM; + + res_ports = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res_ports) + goto err_ports; + + res_result = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res_result) + goto err_ports; + + + rng->control_status = devm_ioremap_nocache(&pdev->dev, + res_ports->start, + sizeof(u64)); + if (!rng->control_status) + goto err_ports; + + rng->result = devm_ioremap_nocache(&pdev->dev, + res_result->start, + sizeof(u64)); + if (!rng->result) + goto err_r; + + rng->ops = ops; + + dev_set_drvdata(&pdev->dev, &rng->ops); + ret = hwrng_register(&rng->ops); + if (ret) + goto err; + + dev_info(&pdev->dev, "Octeon Random Number Generator\n"); + + return 0; +err: + devm_iounmap(&pdev->dev, rng->control_status); +err_r: + devm_iounmap(&pdev->dev, rng->result); +err_ports: + devm_kfree(&pdev->dev, rng); + return -ENOENT; +} + +static int __exit octeon_rng_remove(struct platform_device *pdev) +{ + struct hwrng *rng = dev_get_drvdata(&pdev->dev); + + hwrng_unregister(rng); + + return 0; +} + +static struct platform_driver octeon_rng_driver = { + .driver = { + .name = "octeon_rng", + .owner = THIS_MODULE, + }, + .probe = octeon_rng_probe, + .remove = __exit_p(octeon_rng_remove), +}; + +static int __init octeon_rng_mod_init(void) +{ + return platform_driver_register(&octeon_rng_driver); +} + +static void __exit octeon_rng_mod_exit(void) +{ + platform_driver_unregister(&octeon_rng_driver); +} + +module_init(octeon_rng_mod_init); +module_exit(octeon_rng_mod_exit); + +MODULE_AUTHOR("David Daney"); +MODULE_LICENSE("GPL"); |