[src/trunk]: src/sys/arch/arm/ti Add support for hardware RNG.

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4eee75f0f1fd
branches:  trunk
changeset: 460626:4eee75f0f1fd
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Mon Oct 28 23:57:59 2019 +0000

description:
Add support for hardware RNG.

diffstat:

 sys/arch/arm/ti/am3_prcm.c  |    6 +-
 sys/arch/arm/ti/files.ti    |    7 +-
 sys/arch/arm/ti/ti_rng.c    |  151 ++++++++++++++++++++++++++++++++++++++++++++
 sys/arch/arm/ti/ti_rngreg.h |   44 ++++++++++++
 4 files changed, 205 insertions(+), 3 deletions(-)

diffs (251 lines):

diff -r 34cc4f3dcb26 -r 4eee75f0f1fd sys/arch/arm/ti/am3_prcm.c
--- a/sys/arch/arm/ti/am3_prcm.c        Mon Oct 28 23:32:15 2019 +0000
+++ b/sys/arch/arm/ti/am3_prcm.c        Mon Oct 28 23:57:59 2019 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: am3_prcm.c,v 1.6 2019/10/28 22:21:35 jmcneill Exp $ */
+/* $NetBSD: am3_prcm.c,v 1.7 2019/10/28 23:57:59 jmcneill Exp $ */
 
 /*-
  * Copyright (c) 2017 Jared McNeill <jmcneill%invisible.ca@localhost>
@@ -28,7 +28,7 @@
 
 #include <sys/cdefs.h>
 
-__KERNEL_RCSID(1, "$NetBSD: am3_prcm.c,v 1.6 2019/10/28 22:21:35 jmcneill Exp $");
+__KERNEL_RCSID(1, "$NetBSD: am3_prcm.c,v 1.7 2019/10/28 23:57:59 jmcneill Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -124,6 +124,8 @@
        AM3_PRCM_HWMOD_PER("tptc2", 0x100, "PERIPH_CLK"),
 
        AM3_PRCM_HWMOD_PER("usb_otg_hs", 0x1c, "PERIPH_CLK"),
+
+       AM3_PRCM_HWMOD_PER("rng", 0x90, "PERIPH_CLK"),
 };
 
 static int
diff -r 34cc4f3dcb26 -r 4eee75f0f1fd sys/arch/arm/ti/files.ti
--- a/sys/arch/arm/ti/files.ti  Mon Oct 28 23:32:15 2019 +0000
+++ b/sys/arch/arm/ti/files.ti  Mon Oct 28 23:57:59 2019 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: files.ti,v 1.13 2019/10/28 22:21:35 jmcneill Exp $
+#      $NetBSD: files.ti,v 1.14 2019/10/28 23:57:59 jmcneill Exp $
 #
 
 file   arch/arm/ti/ti_platform.c       soc_ti
@@ -80,6 +80,11 @@
 attach motg at fdt with ti_motg
 file   arch/arm/ti/ti_motg.c           ti_motg
 
+# RNG
+device tirng
+attach tirng at fdt with ti_rng
+file   arch/arm/ti/ti_rng.c            ti_rng
+
 # SOC parameters
 defflag        opt_soc.h                       SOC_TI
 defflag        opt_soc.h                       SOC_TI_AM335X: SOC_TI
diff -r 34cc4f3dcb26 -r 4eee75f0f1fd sys/arch/arm/ti/ti_rng.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/arch/arm/ti/ti_rng.c  Mon Oct 28 23:57:59 2019 +0000
@@ -0,0 +1,151 @@
+/* $NetBSD: ti_rng.c,v 1.1 2019/10/28 23:57:59 jmcneill Exp $ */
+
+/*-
+ * Copyright (c) 2015 Jared D. McNeill <jmcneill%invisible.ca@localhost>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: ti_rng.c,v 1.1 2019/10/28 23:57:59 jmcneill Exp $");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/conf.h>
+#include <sys/mutex.h>
+#include <sys/bus.h>
+#include <sys/rndpool.h>
+#include <sys/rndsource.h>
+
+#include <dev/fdt/fdtvar.h>
+
+#include <arm/ti/ti_prcm.h>
+#include <arm/ti/ti_rngreg.h>
+
+static const char * const compatible[] = {
+       "ti,omap4-rng",
+       NULL
+};
+
+struct ti_rng_softc {
+       device_t sc_dev;
+       bus_space_tag_t sc_iot;
+       bus_space_handle_t sc_ioh;
+
+       kmutex_t sc_lock;
+       krndsource_t sc_rndsource;
+};
+
+static int     ti_rng_match(device_t, cfdata_t, void *);
+static void    ti_rng_attach(device_t, device_t, void *);
+static void    ti_rng_callback(size_t, void *);
+
+CFATTACH_DECL_NEW(ti_rng, sizeof(struct ti_rng_softc),
+    ti_rng_match, ti_rng_attach, NULL, NULL);
+
+#define RD4(sc, reg) \
+       bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg))
+#define WR4(sc, reg, val) \
+       bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val))
+
+static int
+ti_rng_match(device_t parent, cfdata_t match, void *aux)
+{
+       struct fdt_attach_args * const faa = aux;
+
+       return of_match_compatible(faa->faa_phandle, compatible);
+}
+
+static void
+ti_rng_attach(device_t parent, device_t self, void *aux)
+{
+       struct ti_rng_softc *sc = device_private(self);
+       struct fdt_attach_args * const faa = aux;
+       const int phandle = faa->faa_phandle;
+       bus_addr_t addr;
+       bus_size_t size;
+
+       if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
+               aprint_error(": couldn't get registers\n");
+               return;
+       }
+
+       if (ti_prcm_enable_hwmod(OF_parent(phandle), 0) != 0) {
+               aprint_error(": couldn't enable module\n");
+               return;
+       }
+
+       sc->sc_dev = self;
+       sc->sc_iot = faa->faa_bst;
+       if (bus_space_map(sc->sc_iot, addr, size, 0, &sc->sc_ioh) != 0) {
+               aprint_error(": couldn't map registers\n");
+               return;
+       }
+
+       mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
+
+       if ((RD4(sc, TRNG_CONTROL_REG) & TRNG_CONTROL_ENABLE) == 0) {
+               WR4(sc, TRNG_CONFIG_REG,
+                   __SHIFTIN(0x21, TRNG_CONFIG_MIN_REFILL) |
+                   __SHIFTIN(0x22, TRNG_CONFIG_MAX_REFILL));
+               WR4(sc, TRNG_CONTROL_REG,
+                   __SHIFTIN(0x21, TRNG_CONTROL_STARTUP_CYCLES) |
+                   TRNG_CONTROL_ENABLE);
+       }
+
+       rndsource_setcb(&sc->sc_rndsource, ti_rng_callback, sc);
+       rnd_attach_source(&sc->sc_rndsource, device_xname(self), RND_TYPE_RNG,
+           RND_FLAG_COLLECT_VALUE|RND_FLAG_HASCB);
+
+       aprint_naive("\n");
+       aprint_normal(": RNG\n");
+
+       ti_rng_callback(RND_POOLBITS / NBBY, sc);
+}
+
+static void
+ti_rng_callback(size_t bytes_wanted, void *priv)
+{
+       struct ti_rng_softc * const sc = priv;
+       uint32_t buf[2];
+       u_int retry;
+
+       mutex_enter(&sc->sc_lock);
+       while (bytes_wanted) {
+               for (retry = 10; retry > 0; retry--) {
+                       if (RD4(sc, TRNG_STATUS_REG) & TRNG_STATUS_READY)
+                               break;
+                       delay(10);
+               }
+               if (retry == 0)
+                       break;
+               buf[0] = RD4(sc, TRNG_OUTPUT_L_REG);
+               buf[1] = RD4(sc, TRNG_OUTPUT_H_REG);
+               WR4(sc, TRNG_INTACK_REG, TRNG_INTACK_READY);
+               rnd_add_data_sync(&sc->sc_rndsource, buf, sizeof(buf),
+                   sizeof(buf) * NBBY);
+               bytes_wanted -= MIN(bytes_wanted, sizeof(buf));
+       }
+       explicit_memset(buf, 0, sizeof(buf));
+       mutex_exit(&sc->sc_lock);
+}
diff -r 34cc4f3dcb26 -r 4eee75f0f1fd sys/arch/arm/ti/ti_rngreg.h
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/arch/arm/ti/ti_rngreg.h       Mon Oct 28 23:57:59 2019 +0000
@@ -0,0 +1,44 @@
+/* $NetBSD: ti_rngreg.h,v 1.1 2019/10/28 23:57:59 jmcneill Exp $ */
+
+/*-
+ * Copyright (c) 2015 Jared D. McNeill <jmcneill%invisible.ca@localhost>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _TI_RNGREG_H
+#define _TI_RNGREG_H
+
+#define TRNG_OUTPUT_L_REG      0x00
+#define TRNG_OUTPUT_H_REG      0x04
+#define TRNG_STATUS_REG                0x08
+#define TRNG_STATUS_READY              __BIT(0)
+#define TRNG_INTACK_REG                0x10
+#define TRNG_INTACK_READY              __BIT(0)
+#define TRNG_CONTROL_REG       0x14
+#define TRNG_CONTROL_STARTUP_CYCLES    __BITS(31,16)
+#define TRNG_CONTROL_ENABLE            __BIT(10)
+#define TRNG_CONFIG_REG                0x18
+#define TRNG_CONFIG_MAX_REFILL         __BITS(31,16)
+#define TRNG_CONFIG_MIN_REFILL         __BITS(7,0)
+
+#endif /* !_TI_RNGREG_H */