lkml.org 
[lkml]   [2008]   [May]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
Subject[PATCH 2/2]: sparc64: Add Niagara2 RNG driver.
From

Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/char/hw_random/Kconfig | 13 +
drivers/char/hw_random/Makefile | 2 +
drivers/char/hw_random/n2-asm.S | 93 +++++
drivers/char/hw_random/n2-drv.c | 771 +++++++++++++++++++++++++++++++++++++++
drivers/char/hw_random/n2rng.h | 118 ++++++
5 files changed, 997 insertions(+), 0 deletions(-)
create mode 100644 drivers/char/hw_random/n2-asm.S
create mode 100644 drivers/char/hw_random/n2-drv.c
create mode 100644 drivers/char/hw_random/n2rng.h
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 8d6c208..f4aecb6 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -59,6 +59,19 @@ config HW_RANDOM_GEODE

If unsure, say Y.

+config HW_RANDOM_N2RNG
+ tristate "Niagara2 Random Number Generator support"
+ depends on HW_RANDOM && SPARC64
+ default HW_RANDOM
+ ---help---
+ This driver provides kernel-side support for the Random Number
+ Generator hardware found on Niagara2 cpus.
+
+ To compile this driver as a module, choose M here: the
+ module will be called n2-rng.
+
+ If unsure, say Y.
+
config HW_RANDOM_VIA
tristate "VIA HW Random Number Generator support"
depends on HW_RANDOM && X86_32
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index c8b7300..32b327b 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -7,6 +7,8 @@ rng-core-y := core.o
obj-$(CONFIG_HW_RANDOM_INTEL) += intel-rng.o
obj-$(CONFIG_HW_RANDOM_AMD) += amd-rng.o
obj-$(CONFIG_HW_RANDOM_GEODE) += geode-rng.o
+obj-$(CONFIG_HW_RANDOM_N2RNG) += n2-rng.o
+n2-rng-objs := n2-drv.o n2-asm.o
obj-$(CONFIG_HW_RANDOM_VIA) += via-rng.o
obj-$(CONFIG_HW_RANDOM_IXP4XX) += ixp4xx-rng.o
obj-$(CONFIG_HW_RANDOM_OMAP) += omap-rng.o
diff --git a/drivers/char/hw_random/n2-asm.S b/drivers/char/hw_random/n2-asm.S
new file mode 100644
index 0000000..c504e53
--- /dev/null
+++ b/drivers/char/hw_random/n2-asm.S
@@ -0,0 +1,93 @@
+/* n2-asm.S: Niagara2 RNG hypervisor call assembler.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+#include <asm/hypervisor.h>
+#include "n2rng.h"
+
+ .text
+ .globl sun4v_rng_get_diag_ctl
+ .type sun4v_rng_get_diag_ctl,#function
+sun4v_rng_get_diag_ctl:
+ mov HV_FAST_RNG_GET_DIAG_CTL, %o5
+ ta HV_FAST_TRAP
+ retl
+ nop
+ .size sun4v_rng_get_diag_ctl,.-sun4v_rng_get_diag_ctl
+
+ .globl sun4v_rng_ctl_read_v1
+ .type sun4v_rng_ctl_read_v1,#function
+sun4v_rng_ctl_read_v1:
+ mov %o1, %o3
+ mov %o2, %o4
+ mov HV_FAST_RNG_CTL_READ, %o5
+ ta HV_FAST_TRAP
+ stx %o1, [%o3]
+ retl
+ stx %o2, [%o4]
+ .size sun4v_rng_ctl_read_v1,.-sun4v_rng_ctl_read_v1
+
+ .globl sun4v_rng_ctl_read_v2
+ .type sun4v_rng_ctl_read_v2,#function
+sun4v_rng_ctl_read_v2:
+ save %sp, -192, %sp
+ mov %i0, %o0
+ mov %i1, %o1
+ mov HV_FAST_RNG_CTL_READ, %o5
+ ta HV_FAST_TRAP
+ stx %o1, [%i2]
+ stx %o2, [%i3]
+ stx %o3, [%i4]
+ stx %o4, [%i5]
+ ret
+ restore %g0, %o0, %o0
+ .size sun4v_rng_ctl_read_v2,.-sun4v_rng_ctl_read_v2
+
+ .globl sun4v_rng_ctl_write_v1
+ .type sun4v_rng_ctl_write_v1,#function
+sun4v_rng_ctl_write_v1:
+ mov %o3, %o4
+ mov HV_FAST_RNG_CTL_WRITE, %o5
+ ta HV_FAST_TRAP
+ retl
+ stx %o1, [%o4]
+ .size sun4v_rng_ctl_write_v1,.-sun4v_rng_ctl_write_v1
+
+ .globl sun4v_rng_ctl_write_v2
+ .type sun4v_rng_ctl_write_v2,#function
+sun4v_rng_ctl_write_v2:
+ mov HV_FAST_RNG_CTL_WRITE, %o5
+ ta HV_FAST_TRAP
+ retl
+ nop
+ .size sun4v_rng_ctl_write_v2,.-sun4v_rng_ctl_write_v2
+
+ .globl sun4v_rng_data_read_diag_v1
+ .type sun4v_rng_data_read_diag_v1,#function
+sun4v_rng_data_read_diag_v1:
+ mov %o2, %o4
+ mov HV_FAST_RNG_DATA_READ_DIAG, %o5
+ ta HV_FAST_TRAP
+ retl
+ stx %o1, [%o4]
+ .size sun4v_rng_data_read_diag_v1,.-sun4v_rng_data_read_diag_v1
+
+ .globl sun4v_rng_data_read_diag_v2
+ .type sun4v_rng_data_read_diag_v2,#function
+sun4v_rng_data_read_diag_v2:
+ mov %o3, %o4
+ mov HV_FAST_RNG_DATA_READ_DIAG, %o5
+ ta HV_FAST_TRAP
+ retl
+ stx %o1, [%o4]
+ .size sun4v_rng_data_read_diag_v2,.-sun4v_rng_data_read_diag_v2
+
+ .globl sun4v_rng_data_read
+ .type sun4v_rng_data_read,#function
+sun4v_rng_data_read:
+ mov %o1, %o4
+ mov HV_FAST_RNG_DATA_READ, %o5
+ ta HV_FAST_TRAP
+ retl
+ stx %o1, [%o4]
+ .size sun4v_rng_data_read,.-sun4v_rng_data_read
diff --git a/drivers/char/hw_random/n2-drv.c b/drivers/char/hw_random/n2-drv.c
new file mode 100644
index 0000000..5220f54
--- /dev/null
+++ b/drivers/char/hw_random/n2-drv.c
@@ -0,0 +1,771 @@
+/* n2-drv.c: Niagara-2 RNG driver.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/preempt.h>
+#include <linux/hw_random.h>
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <asm/hypervisor.h>
+
+#include "n2rng.h"
+
+#define DRV_MODULE_NAME "n2rng"
+#define PFX DRV_MODULE_NAME ": "
+#define DRV_MODULE_VERSION "0.1"
+#define DRV_MODULE_RELDATE "May 15, 2008"
+
+static char version[] __devinitdata =
+ DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
+
+MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
+MODULE_DESCRIPTION("Niagara2 RNG driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_MODULE_VERSION);
+
+/* The Niagara2 RNG provides a 64-bit read-only random number
+ * register, plus a control register. Access to the RNG is
+ * virtualized through the hypervisor so that both guests and control
+ * nodes can access the device.
+ *
+ * The entropy source consists of raw entropy sources, each
+ * constructed from a voltage controlled oscillator whose phase is
+ * jittered by thermal noise sources.
+ *
+ * The oscillator in each of the three raw entropy sources run at
+ * different frequencies. Normally, all three generator outputs are
+ * gathered, xored together, and fed into a CRC circuit, the output of
+ * which is the 64-bit read-only register.
+ *
+ * Some time is necessary for all the necessary entropy to build up
+ * such that a full 64-bits of entropy are available in the register.
+ * In normal operating mode (RNG_CTL_LFSR is set), the chip implements
+ * an interlock which blocks register reads until sufficient entropy
+ * is available.
+ *
+ * A control register is provided for adjusting various aspects of RNG
+ * operation, and to enable diagnostic modes. Each of the three raw
+ * entropy sources has an enable bit (RNG_CTL_ES{1,2,3}). Also
+ * provided are fields for controlling the minimum time in cycles
+ * between read accesses to the register (RNG_CTL_WAIT, this controls
+ * the interlock described in the previous paragraph).
+ *
+ * The standard setting is to have the mode bit (RNG_CTL_LFSR) set,
+ * all three entropy sources enabled, and the interlock time set
+ * appropriately.
+ *
+ * The CRC polynomial used by the chip is:
+ *
+ * P(X) = x64 + x61 + x57 + x56 + x52 + x51 + x50 + x48 + x47 + x46 +
+ * x43 + x42 + x41 + x39 + x38 + x37 + x35 + x32 + x28 + x25 +
+ * x22 + x21 + x17 + x15 + x13 + x12 + x11 + x7 + x5 + x + 1
+ *
+ * The RNG_CTL_VCO value of each noise cell must be programmed
+ * seperately. This is why 4 control register values must be provided
+ * to the hypervisor. During a write, the hypervisor writes them all,
+ * one at a time, to the actual RNG_CTL register. The first three
+ * values are used to setup the desired RNG_CTL_VCO for each entropy
+ * source, for example:
+ *
+ * control 0: (1 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES1
+ * control 1: (2 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES2
+ * control 2: (3 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES3
+ *
+ * And then the fourth value sets the final chip state and enables
+ * desired.
+ */
+
+static int n2rng_hv_err_trans(unsigned long hv_err)
+{
+ switch (hv_err) {
+ case HV_EOK:
+ return 0;
+ case HV_EWOULDBLOCK:
+ return -EAGAIN;
+ case HV_ENOACCESS:
+ return -EPERM;
+ case HV_EIO:
+ return -EIO;
+ case HV_EBUSY:
+ return -EBUSY;
+ case HV_EBADALIGN:
+ case HV_ENORADDR:
+ return -EFAULT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static unsigned long n2rng_generic_read_control_v2(unsigned long ra,
+ unsigned long unit)
+{
+ unsigned long hv_err, state, ticks, watchdog_delta, watchdog_status;
+ int block = 0, busy = 0;
+
+ while (1) {
+ hv_err = sun4v_rng_ctl_read_v2(ra, unit, &state,
+ &ticks,
+ &watchdog_delta,
+ &watchdog_status);
+ if (hv_err == HV_EOK)
+ break;
+
+ if (hv_err == HV_EBUSY) {
+ if (++busy >= N2RNG_BUSY_LIMIT)
+ break;
+
+ udelay(1);
+ } else if (hv_err == HV_EWOULDBLOCK) {
+ if (++block >= N2RNG_BLOCK_LIMIT)
+ break;
+
+ __delay(ticks);
+ } else
+ break;
+ }
+
+ return hv_err;
+}
+
+/* In multi-socket situations, the hypervisor might need to
+ * queue up the RNG control register write if it's for a unit
+ * that is on a cpu socket other than the one we are executing on.
+ *
+ * We poll here waiting for a successful read of that control
+ * register to make sure the write has been actually performed.
+ */
+static unsigned long n2rng_control_settle_v2(struct n2rng *np, int unit)
+{
+ unsigned long ra = __pa(&np->scratch_control[0]);
+
+ return n2rng_generic_read_control_v2(ra, unit);
+}
+
+static unsigned long n2rng_write_ctl_one(struct n2rng *np, int unit,
+ unsigned long state,
+ unsigned long control_ra,
+ unsigned long watchdog_timeout,
+ unsigned long *ticks)
+{
+ unsigned long hv_err;
+
+ if (np->hvapi_major == 1) {
+ hv_err = sun4v_rng_ctl_write_v1(control_ra, state,
+ watchdog_timeout, ticks);
+ } else {
+ hv_err = sun4v_rng_ctl_write_v2(control_ra, state,
+ watchdog_timeout, unit);
+ if (hv_err == HV_EOK)
+ hv_err = n2rng_control_settle_v2(np, unit);
+ *ticks = N2RNG_ACCUM_CYCLES_DEFAULT;
+ }
+
+ return hv_err;
+}
+
+static int n2rng_generic_read_data(unsigned long data_ra)
+{
+ unsigned long ticks, hv_err;
+ int block = 0, hcheck = 0;
+
+ while (1) {
+ hv_err = sun4v_rng_data_read(data_ra, &ticks);
+ if (hv_err == HV_EOK)
+ return 0;
+
+ if (hv_err == HV_EWOULDBLOCK) {
+ if (++block >= N2RNG_BLOCK_LIMIT)
+ return -EWOULDBLOCK;
+ __delay(ticks);
+ } else if (hv_err == HV_ENOACCESS) {
+ return -EPERM;
+ } else if (hv_err == HV_EIO) {
+ if (++hcheck >= N2RNG_HCHECK_LIMIT)
+ return -EIO;
+ udelay(10000);
+ } else
+ return -ENODEV;
+ }
+}
+
+static unsigned long n2rng_read_diag_data_one(struct n2rng *np,
+ unsigned long unit,
+ unsigned long data_ra,
+ unsigned long data_len,
+ unsigned long *ticks)
+{
+ unsigned long hv_err;
+
+ if (np->hvapi_major == 1) {
+ hv_err = sun4v_rng_data_read_diag_v1(data_ra, data_len, ticks);
+ } else {
+ hv_err = sun4v_rng_data_read_diag_v2(data_ra, data_len,
+ unit, ticks);
+ if (!*ticks)
+ *ticks = N2RNG_ACCUM_CYCLES_DEFAULT;
+ }
+ return hv_err;
+}
+
+static int n2rng_generic_read_diag_data(struct n2rng *np,
+ unsigned long unit,
+ unsigned long data_ra,
+ unsigned long data_len)
+{
+ unsigned long ticks, hv_err;
+ int block = 0;
+
+ while (1) {
+ hv_err = n2rng_read_diag_data_one(np, unit,
+ data_ra, data_len,
+ &ticks);
+ if (hv_err == HV_EOK)
+ return 0;
+
+ if (hv_err == HV_EWOULDBLOCK) {
+ if (++block >= N2RNG_BLOCK_LIMIT)
+ return -EWOULDBLOCK;
+ __delay(ticks);
+ } else if (hv_err == HV_ENOACCESS) {
+ return -EPERM;
+ } else if (hv_err == HV_EIO) {
+ return -EIO;
+ } else
+ return -ENODEV;
+ }
+}
+
+
+static int n2rng_generic_write_control(struct n2rng *np,
+ unsigned long control_ra,
+ unsigned long unit,
+ unsigned long state)
+{
+ unsigned long hv_err, ticks;
+ int block = 0, busy = 0;
+
+ while (1) {
+ hv_err = n2rng_write_ctl_one(np, unit, state, control_ra,
+ np->wd_timeo, &ticks);
+ if (hv_err == HV_EOK)
+ return 0;
+
+ if (hv_err == HV_EWOULDBLOCK) {
+ if (++block >= N2RNG_BLOCK_LIMIT)
+ return -EWOULDBLOCK;
+ __delay(ticks);
+ } else if (hv_err == HV_EBUSY) {
+ if (++busy >= N2RNG_BUSY_LIMIT)
+ return -EBUSY;
+ udelay(1);
+ } else
+ return -ENODEV;
+ }
+}
+
+/* Just try to see if we can successfully access the control register
+ * of the RNG on the domain on which we are currently executing.
+ */
+static int n2rng_try_read_ctl(struct n2rng *np)
+{
+ unsigned long hv_err;
+ unsigned long x;
+
+ if (np->hvapi_major == 1) {
+ hv_err = sun4v_rng_get_diag_ctl();
+ } else {
+ /* We purposefully give invalid arguments, HV_NOACCESS
+ * is higher priority than the errors we'd get from
+ * these other cases, and that's the error we are
+ * truly interested in.
+ */
+ hv_err = sun4v_rng_ctl_read_v2(0UL, ~0UL, &x, &x, &x, &x);
+ switch (hv_err) {
+ case HV_EWOULDBLOCK:
+ case HV_ENOACCESS:
+ break;
+ default:
+ hv_err = HV_EOK;
+ break;
+ }
+ }
+
+ return n2rng_hv_err_trans(hv_err);
+}
+
+#define CONTROL_DEFAULT_BASE \
+ ((2 << RNG_CTL_ASEL_SHIFT) | \
+ (N2RNG_ACCUM_CYCLES_DEFAULT << RNG_CTL_WAIT_SHIFT) | \
+ RNG_CTL_LFSR)
+
+#define CONTROL_DEFAULT_0 \
+ (CONTROL_DEFAULT_BASE | \
+ (1 << RNG_CTL_VCO_SHIFT) | \
+ RNG_CTL_ES1)
+#define CONTROL_DEFAULT_1 \
+ (CONTROL_DEFAULT_BASE | \
+ (2 << RNG_CTL_VCO_SHIFT) | \
+ RNG_CTL_ES2)
+#define CONTROL_DEFAULT_2 \
+ (CONTROL_DEFAULT_BASE | \
+ (3 << RNG_CTL_VCO_SHIFT) | \
+ RNG_CTL_ES3)
+#define CONTROL_DEFAULT_3 \
+ (CONTROL_DEFAULT_BASE | \
+ RNG_CTL_ES1 | RNG_CTL_ES2 | RNG_CTL_ES3)
+
+static void n2rng_control_swstate_init(struct n2rng *np)
+{
+ int i;
+
+ np->flags |= N2RNG_FLAG_CONTROL;
+
+ np->health_check_sec = N2RNG_HEALTH_CHECK_SEC_DEFAULT;
+ np->accum_cycles = N2RNG_ACCUM_CYCLES_DEFAULT;
+ np->wd_timeo = N2RNG_WD_TIMEO_DEFAULT;
+
+ for (i = 0; i < np->num_units; i++) {
+ struct n2rng_unit *up = &np->units[i];
+
+ up->control[0] = CONTROL_DEFAULT_0;
+ up->control[1] = CONTROL_DEFAULT_1;
+ up->control[2] = CONTROL_DEFAULT_2;
+ up->control[3] = CONTROL_DEFAULT_3;
+ }
+
+ np->hv_state = HV_RNG_STATE_UNCONFIGURED;
+}
+
+static int n2rng_grab_diag_control(struct n2rng *np)
+{
+ int i, busy_count, err = -ENODEV;
+
+ busy_count = 0;
+ for (i = 0; i < 100; i++) {
+ err = n2rng_try_read_ctl(np);
+ if (err != -EAGAIN)
+ break;
+
+ if (++busy_count > 100) {
+ dev_err(&np->op->dev,
+ "Grab diag control timeout.\n");
+ return -ENODEV;
+ }
+
+ udelay(1);
+ }
+
+ return err;
+}
+
+static int n2rng_init_control(struct n2rng *np)
+{
+ int err = n2rng_grab_diag_control(np);
+
+ /* Not in the control domain, that's OK we are only a consumer
+ * of the RNG data, we don't setup and program it.
+ */
+ if (err == -EPERM)
+ return 0;
+ if (err)
+ return err;
+
+ n2rng_control_swstate_init(np);
+
+ return 0;
+}
+
+static int n2rng_data_read(struct hwrng *rng, u32 *data)
+{
+ struct n2rng *np = (struct n2rng *) rng->priv;
+ unsigned long ra = __pa(&np->test_data);
+ int len;
+
+ if (!(np->flags & N2RNG_FLAG_READY)) {
+ len = 0;
+ } else if (np->flags & N2RNG_FLAG_BUFFER_VALID) {
+ np->flags &= ~N2RNG_FLAG_BUFFER_VALID;
+ *data = np->buffer;
+ len = 4;
+ } else {
+ int err = n2rng_generic_read_data(ra);
+ if (!err) {
+ np->buffer = np->test_data >> 32;
+ *data = np->test_data & 0xffffffff;
+ len = 4;
+ } else {
+ dev_err(&np->op->dev, "RNG error, restesting\n");
+ np->flags &= ~N2RNG_FLAG_READY;
+ if (!(np->flags & N2RNG_FLAG_SHUTDOWN))
+ schedule_delayed_work(&np->work, 0);
+ len = 0;
+ }
+ }
+
+ return len;
+}
+
+/* On a guest node, just make sure we can read random data properly.
+ * If a control node reboots or reloads it's n2rng driver, this won't
+ * work during that time. So we have to keep probing until the device
+ * becomes usable.
+ */
+static int n2rng_guest_check(struct n2rng *np)
+{
+ unsigned long ra = __pa(&np->test_data);
+
+ return n2rng_generic_read_data(ra);
+}
+
+static int n2rng_entropy_diag_read(struct n2rng *np, unsigned long unit,
+ u64 *pre_control, u64 pre_state,
+ u64 *buffer, unsigned long buf_len,
+ u64 *post_control, u64 post_state)
+{
+ unsigned long post_ctl_ra = __pa(post_control);
+ unsigned long pre_ctl_ra = __pa(pre_control);
+ unsigned long buffer_ra = __pa(buffer);
+ int err;
+
+ err = n2rng_generic_write_control(np, pre_ctl_ra, unit, pre_state);
+ if (err)
+ return err;
+
+ err = n2rng_generic_read_diag_data(np, unit,
+ buffer_ra, buf_len);
+
+ (void) n2rng_generic_write_control(np, post_ctl_ra, unit,
+ post_state);
+
+ return err;
+}
+
+static u64 advance_polynomial(u64 poly, u64 val, int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ int highbit_set = ((s64)val < 0);
+
+ val <<= 1;
+ if (highbit_set)
+ val ^= poly;
+ }
+
+ return val;
+}
+
+static int n2rng_test_buffer_find(struct n2rng *np, u64 val)
+{
+ int i, count = 0;
+
+ /* Purposefully skip over the first word. */
+ for (i = 1; i < SELFTEST_BUFFER_WORDS; i++) {
+ if (np->test_buffer[i] == val)
+ count++;
+ }
+ return count;
+}
+
+static void n2rng_dump_test_buffer(struct n2rng *np)
+{
+ int i;
+
+ for (i = 0; i < SELFTEST_BUFFER_WORDS; i++)
+ dev_err(&np->op->dev, "Test buffer slot %d [0x%016lx]\n",
+ i, np->test_buffer[i]);
+}
+
+static int n2rng_check_selftest_buffer(struct n2rng *np, unsigned long unit)
+{
+ u64 val = SELFTEST_VAL;
+ int err, matches, limit;
+
+ matches = 0;
+ for (limit = 0; limit < SELFTEST_LOOPS_MAX; limit++) {
+ matches += n2rng_test_buffer_find(np, val);
+ if (matches >= SELFTEST_MATCH_GOAL)
+ break;
+ val = advance_polynomial(SELFTEST_POLY, val, 1);
+ }
+
+ err = 0;
+ if (limit >= SELFTEST_LOOPS_MAX) {
+ err = -ENODEV;
+ dev_err(&np->op->dev, "Selftest failed on unit %lu\n", unit);
+ n2rng_dump_test_buffer(np);
+ } else
+ dev_info(&np->op->dev, "Selftest passed on unit %lu\n", unit);
+
+ return err;
+}
+
+static int n2rng_control_selftest(struct n2rng *np, unsigned long unit)
+{
+ int err;
+
+ np->test_control[0] = (0x2 << RNG_CTL_ASEL_SHIFT);
+ np->test_control[1] = (0x2 << RNG_CTL_ASEL_SHIFT);
+ np->test_control[2] = (0x2 << RNG_CTL_ASEL_SHIFT);
+ np->test_control[3] = ((0x2 << RNG_CTL_ASEL_SHIFT) |
+ RNG_CTL_LFSR |
+ ((SELFTEST_TICKS - 2) << RNG_CTL_WAIT_SHIFT));
+
+
+ err = n2rng_entropy_diag_read(np, unit, np->test_control,
+ HV_RNG_STATE_HEALTHCHECK,
+ np->test_buffer,
+ sizeof(np->test_buffer),
+ &np->units[unit].control[0],
+ np->hv_state);
+ if (err)
+ return err;
+
+ return n2rng_check_selftest_buffer(np, unit);
+}
+
+static int n2rng_control_check(struct n2rng *np)
+{
+ int i;
+
+ for (i = 0; i < np->num_units; i++) {
+ int err = n2rng_control_selftest(np, i);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+/* The sanity checks passed, install the final configuration into the
+ * chip, it's ready to use.
+ */
+static int n2rng_control_configure_units(struct n2rng *np)
+{
+ int unit, err;
+
+ err = 0;
+ for (unit = 0; unit < np->num_units; unit++) {
+ struct n2rng_unit *up = &np->units[unit];
+ unsigned long ctl_ra = __pa(&up->control[0]);
+ int esrc;
+ u64 base;
+
+ base = ((np->accum_cycles << RNG_CTL_WAIT_SHIFT) |
+ (2 << RNG_CTL_ASEL_SHIFT) |
+ RNG_CTL_LFSR);
+
+ /* XXX This isn't the best. We should fetch a bunch
+ * XXX of words using each entropy source combined XXX
+ * with each VCO setting, and see which combinations
+ * XXX give the best random data.
+ */
+ for (esrc = 0; esrc < 3; esrc++)
+ up->control[esrc] = base |
+ (esrc << RNG_CTL_VCO_SHIFT) |
+ (RNG_CTL_ES1 << esrc);
+
+ up->control[3] = base |
+ (RNG_CTL_ES1 | RNG_CTL_ES2 | RNG_CTL_ES3);
+
+ err = n2rng_generic_write_control(np, ctl_ra, unit,
+ HV_RNG_STATE_CONFIGURED);
+ if (err)
+ break;
+ }
+
+ return err;
+}
+
+static void n2rng_work(struct work_struct *work)
+{
+ struct n2rng *np = container_of(work, struct n2rng, work.work);
+ int err = 0;
+
+ if (!(np->flags & N2RNG_FLAG_CONTROL)) {
+ err = n2rng_guest_check(np);
+ } else {
+ preempt_disable();
+ err = n2rng_control_check(np);
+ preempt_enable();
+
+ if (!err)
+ err = n2rng_control_configure_units(np);
+ }
+
+ if (!err) {
+ np->flags |= N2RNG_FLAG_READY;
+ dev_info(&np->op->dev, "RNG ready\n");
+ }
+
+ if (err && !(np->flags & N2RNG_FLAG_SHUTDOWN))
+ schedule_delayed_work(&np->work, HZ * 2);
+}
+
+static void __devinit n2rng_driver_version(void)
+{
+ static int n2rng_version_printed;
+
+ if (n2rng_version_printed++ == 0)
+ pr_info("%s", version);
+}
+
+static int __devinit n2rng_probe(struct of_device *op,
+ const struct of_device_id *match)
+{
+ int victoria_falls = (match->data != NULL);
+ int err = -ENOMEM;
+ struct n2rng *np;
+
+ n2rng_driver_version();
+
+ np = kzalloc(sizeof(*np), GFP_KERNEL);
+ if (!np)
+ goto out;
+ np->op = op;
+
+ INIT_DELAYED_WORK(&np->work, n2rng_work);
+
+ if (victoria_falls)
+ np->flags |= N2RNG_FLAG_VF;
+
+ err = -ENODEV;
+ np->hvapi_major = 2;
+ if (sun4v_hvapi_register(HV_GRP_RNG,
+ np->hvapi_major,
+ &np->hvapi_minor)) {
+ np->hvapi_major = 1;
+ if (sun4v_hvapi_register(HV_GRP_RNG,
+ np->hvapi_major,
+ &np->hvapi_minor)) {
+ dev_err(&op->dev, "Cannot register suitable "
+ "HVAPI version.\n");
+ goto out_free;
+ }
+ }
+
+ if (np->flags & N2RNG_FLAG_VF) {
+ if (np->hvapi_major < 2) {
+ dev_err(&op->dev, "VF RNG requires HVAPI major "
+ "version 2 or later, got %lu\n",
+ np->hvapi_major);
+ goto out_hvapi_unregister;
+ }
+ np->num_units = of_getintprop_default(op->node,
+ "rng-#units", 0);
+ if (!np->num_units) {
+ dev_err(&op->dev, "VF RNG lacks rng-#units property\n");
+ goto out_hvapi_unregister;
+ }
+ } else
+ np->num_units = 1;
+
+ dev_info(&op->dev, "Registered RNG HVAPI major %lu minor %lu\n",
+ np->hvapi_major, np->hvapi_minor);
+
+ np->units = kzalloc(sizeof(struct n2rng_unit) * np->num_units,
+ GFP_KERNEL);
+ err = -ENOMEM;
+ if (!np->units)
+ goto out_hvapi_unregister;
+
+ err = n2rng_init_control(np);
+ if (err)
+ goto out_free_units;
+
+ dev_info(&op->dev, "Found %s RNG, units: %d\n",
+ ((np->flags & N2RNG_FLAG_VF) ?
+ "Victoria Falls" : "Niagara2"),
+ np->num_units);
+
+ np->hwrng.name = "n2rng";
+ np->hwrng.data_read = n2rng_data_read;
+ np->hwrng.priv = (unsigned long) np;
+
+ err = hwrng_register(&np->hwrng);
+ if (err)
+ goto out_free_units;
+
+ dev_set_drvdata(&op->dev, np);
+
+ schedule_delayed_work(&np->work, 0);
+
+ return 0;
+
+out_free_units:
+ kfree(np->units);
+ np->units = NULL;
+
+out_hvapi_unregister:
+ sun4v_hvapi_unregister(HV_GRP_RNG);
+
+out_free:
+ kfree(np);
+out:
+ return err;
+}
+
+static int __devexit n2rng_remove(struct of_device *op)
+{
+ struct n2rng *np = dev_get_drvdata(&op->dev);
+
+ np->flags |= N2RNG_FLAG_SHUTDOWN;
+
+ cancel_delayed_work_sync(&np->work);
+
+ hwrng_unregister(&np->hwrng);
+
+ sun4v_hvapi_unregister(HV_GRP_RNG);
+
+ kfree(np->units);
+ np->units = NULL;
+
+ kfree(np);
+
+ dev_set_drvdata(&op->dev, NULL);
+
+ return 0;
+}
+
+static struct of_device_id n2rng_match[] = {
+ {
+ .name = "random-number-generator",
+ .compatible = "SUNW,n2-rng",
+ },
+ {
+ .name = "random-number-generator",
+ .compatible = "SUNW,vf-rng",
+ .data = (void *) 1,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, n2rng_match);
+
+static struct of_platform_driver n2rng_driver = {
+ .name = "n2rng",
+ .match_table = n2rng_match,
+ .probe = n2rng_probe,
+ .remove = __devexit_p(n2rng_remove),
+};
+
+static int __init n2rng_init(void)
+{
+ return of_register_driver(&n2rng_driver, &of_bus_type);
+}
+
+static void __exit n2rng_exit(void)
+{
+ of_unregister_driver(&n2rng_driver);
+}
+
+module_init(n2rng_init);
+module_exit(n2rng_exit);
diff --git a/drivers/char/hw_random/n2rng.h b/drivers/char/hw_random/n2rng.h
new file mode 100644
index 0000000..a2b81e7
--- /dev/null
+++ b/drivers/char/hw_random/n2rng.h
@@ -0,0 +1,118 @@
+/* n2rng.h: Niagara2 RNG defines.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#ifndef _N2RNG_H
+#define _N2RNG_H
+
+#define RNG_CTL_WAIT 0x0000000001fffe00ULL /* Minimum wait time */
+#define RNG_CTL_WAIT_SHIFT 9
+#define RNG_CTL_BYPASS 0x0000000000000100ULL /* VCO voltage source */
+#define RNG_CTL_VCO 0x00000000000000c0ULL /* VCO rate control */
+#define RNG_CTL_VCO_SHIFT 6
+#define RNG_CTL_ASEL 0x0000000000000030ULL /* Analog MUX select */
+#define RNG_CTL_ASEL_SHIFT 4
+#define RNG_CTL_LFSR 0x0000000000000008ULL /* Use LFSR or plain shift */
+#define RNG_CTL_ES3 0x0000000000000004ULL /* Enable entropy source 3 */
+#define RNG_CTL_ES2 0x0000000000000002ULL /* Enable entropy source 2 */
+#define RNG_CTL_ES1 0x0000000000000001ULL /* Enable entropy source 1 */
+
+#define HV_FAST_RNG_GET_DIAG_CTL 0x130
+#define HV_FAST_RNG_CTL_READ 0x131
+#define HV_FAST_RNG_CTL_WRITE 0x132
+#define HV_FAST_RNG_DATA_READ_DIAG 0x133
+#define HV_FAST_RNG_DATA_READ 0x134
+
+#define HV_RNG_STATE_UNCONFIGURED 0
+#define HV_RNG_STATE_CONFIGURED 1
+#define HV_RNG_STATE_HEALTHCHECK 2
+#define HV_RNG_STATE_ERROR 3
+
+#define HV_RNG_NUM_CONTROL 4
+
+#ifndef __ASSEMBLY__
+extern unsigned long sun4v_rng_get_diag_ctl(void);
+extern unsigned long sun4v_rng_ctl_read_v1(unsigned long ctl_regs_ra,
+ unsigned long *state,
+ unsigned long *tick_delta);
+extern unsigned long sun4v_rng_ctl_read_v2(unsigned long ctl_regs_ra,
+ unsigned long unit,
+ unsigned long *state,
+ unsigned long *tick_delta,
+ unsigned long *watchdog,
+ unsigned long *write_status);
+extern unsigned long sun4v_rng_ctl_write_v1(unsigned long ctl_regs_ra,
+ unsigned long state,
+ unsigned long write_timeout,
+ unsigned long *tick_delta);
+extern unsigned long sun4v_rng_ctl_write_v2(unsigned long ctl_regs_ra,
+ unsigned long state,
+ unsigned long write_timeout,
+ unsigned long unit);
+extern unsigned long sun4v_rng_data_read_diag_v1(unsigned long data_ra,
+ unsigned long len,
+ unsigned long *tick_delta);
+extern unsigned long sun4v_rng_data_read_diag_v2(unsigned long data_ra,
+ unsigned long len,
+ unsigned long unit,
+ unsigned long *tick_delta);
+extern unsigned long sun4v_rng_data_read(unsigned long data_ra,
+ unsigned long *tick_delta);
+
+struct n2rng_unit {
+ u64 control[HV_RNG_NUM_CONTROL];
+};
+
+struct n2rng {
+ struct of_device *op;
+
+ unsigned long flags;
+#define N2RNG_FLAG_VF 0x00000001 /* Victoria Falls RNG, else N2 */
+#define N2RNG_FLAG_CONTROL 0x00000002 /* Operating in control domain */
+#define N2RNG_FLAG_READY 0x00000008 /* Ready for hw-rng layer */
+#define N2RNG_FLAG_SHUTDOWN 0x00000010 /* Driver unregistering */
+#define N2RNG_FLAG_BUFFER_VALID 0x00000020 /* u32 buffer holds valid data */
+
+ int num_units;
+ struct n2rng_unit *units;
+
+ struct hwrng hwrng;
+ u32 buffer;
+
+ /* Registered hypervisor group API major and minor version. */
+ unsigned long hvapi_major;
+ unsigned long hvapi_minor;
+
+ struct delayed_work work;
+
+ unsigned long hv_state; /* HV_RNG_STATE_foo */
+
+ unsigned long health_check_sec;
+ unsigned long accum_cycles;
+ unsigned long wd_timeo;
+#define N2RNG_HEALTH_CHECK_SEC_DEFAULT 0
+#define N2RNG_ACCUM_CYCLES_DEFAULT 2048
+#define N2RNG_WD_TIMEO_DEFAULT 0
+
+ u64 scratch_control[HV_RNG_NUM_CONTROL];
+
+#define SELFTEST_TICKS 38859
+#define SELFTEST_VAL ((u64)0xB8820C7BD387E32C)
+#define SELFTEST_POLY ((u64)0x231DCEE91262B8A3)
+#define SELFTEST_MATCH_GOAL 6
+#define SELFTEST_LOOPS_MAX 40000
+#define SELFTEST_BUFFER_WORDS 8
+
+ u64 test_data;
+ u64 test_control[HV_RNG_NUM_CONTROL];
+ u64 test_buffer[SELFTEST_BUFFER_WORDS];
+};
+
+#define N2RNG_BLOCK_LIMIT 60000
+#define N2RNG_BUSY_LIMIT 100
+#define N2RNG_HCHECK_LIMIT 100
+
+#endif /* !(__ASSEMBLY__) */
+
+#endif /* _N2RNG_H */
--
1.5.5.1.57.g5909c


\
 
 \ /
  Last update: 2008-05-17 01:57    [W:0.084 / U:0.080 seconds]
©2003-2011 Jasper Spaans. Advertise on this site