Add aplefuse(4), a driver for the eFuses on Apple Silicon SoCs.

ok patrick@

diff --git a/sys/arch/arm64/conf/GENERIC b/sys/arch/arm64/conf/GENERIC
index d6608a8..9788fcf 100644 (file)
--- a/sys/arch/arm64/conf/GENERIC
+++ b/sys/arch/arm64/conf/GENERIC
@@ -1,4 +1,4 @@
-# $OpenBSD: GENERIC,v 1.250 2022/12/12 19:18:25 kettenis Exp $
+# $OpenBSD: GENERIC,v 1.251 2022/12/17 11:56:44 kettenis Exp $
 #
 # GENERIC machine description file
 #
@@ -157,6 +157,7 @@ apldcms*    at apldchidev?
 wsmouse*       at apldcms? mux 0
 apldma*                at fdt?
 apldog*                at fdt? early 1
+aplefuse*      at fdt? early 1
 apliic*                at fdt?
 iic*           at apliic?
 aplintc*       at fdt? early 1

diff --git a/sys/arch/arm64/conf/files.arm64 b/sys/arch/arm64/conf/files.arm64
index f5e39df..b30947a 100644 (file)
--- a/sys/arch/arm64/conf/files.arm64
+++ b/sys/arch/arm64/conf/files.arm64
@@ -1,4 +1,4 @@
-# $OpenBSD: files.arm64,v 1.64 2022/11/21 21:48:06 kettenis Exp $
+# $OpenBSD: files.arm64,v 1.65 2022/12/17 11:56:44 kettenis Exp $
 
 maxpartitions  16
 maxusers       2 8 128
@@ -169,6 +169,10 @@ device     apldog
 attach apldog at fdt
 file   arch/arm64/dev/apldog.c                 apldog
 
+device aplefuse
+attach aplefuse at fdt
+file   arch/arm64/dev/aplefuse.c               aplefuse
+
 device apliic: i2cbus
 attach apliic at fdt
 file   arch/arm64/dev/apliic.c                 apliic

diff --git a/sys/arch/arm64/dev/aplefuse.c b/sys/arch/arm64/dev/aplefuse.c
new file mode 100644 (file)
index 0000000..53eb1e4
--- /dev/null
+++ b/sys/arch/arm64/dev/aplefuse.c
@@ -0,0 +1,112 @@
+/*     $OpenBSD: aplefuse.c,v 1.1 2022/12/17 11:56:44 kettenis Exp $   */
+/*
+ * Copyright (c) 2022 Mark Kettenis <kettenis@openbsd.org>
+ *
+ * Permission to use, copy, modify, and 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" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+
+#include <machine/bus.h>
+#include <machine/fdt.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_misc.h>
+#include <dev/ofw/fdt.h>
+
+struct aplefuse_softc {
+       struct device           sc_dev;
+       bus_space_tag_t         sc_iot;
+       bus_space_handle_t      sc_ioh;
+       bus_size_t              sc_ios;
+
+       struct nvmem_device     sc_nd;
+};
+
+int    aplefuse_match(struct device *, void *, void *);
+void   aplefuse_attach(struct device *, struct device *, void *);
+
+const struct cfattach aplefuse_ca = {
+       sizeof (struct aplefuse_softc), aplefuse_match, aplefuse_attach
+};
+
+struct cfdriver aplefuse_cd = {
+       NULL, "aplefuse", DV_DULL
+};
+
+int    aplefuse_nvmem_read(void *, bus_addr_t, void *, bus_size_t);
+int    aplefuse_nvmem_write(void *, bus_addr_t, const void *, bus_size_t);
+
+int
+aplefuse_match(struct device *parent, void *match, void *aux)
+{
+       struct fdt_attach_args *faa = aux;
+
+       return OF_is_compatible(faa->fa_node, "apple,efuses");
+}
+
+void
+aplefuse_attach(struct device *parent, struct device *self, void *aux)
+{
+       struct aplefuse_softc *sc = (struct aplefuse_softc *)self;
+       struct fdt_attach_args *faa = aux;
+
+       if (faa->fa_nreg < 1) {
+               printf(": no registers\n");
+               return;
+       }
+
+       sc->sc_iot = faa->fa_iot;
+       if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
+           faa->fa_reg[0].size, 0, &sc->sc_ioh)) {
+               printf(": can't map registers\n");
+               return;
+       }
+       sc->sc_ios = faa->fa_reg[0].size;
+
+       printf("\n");
+
+       sc->sc_nd.nd_node = faa->fa_node;
+       sc->sc_nd.nd_cookie = sc;
+       sc->sc_nd.nd_read = aplefuse_nvmem_read;
+       nvmem_register(&sc->sc_nd);
+}
+
+int
+aplefuse_nvmem_read(void *cookie, bus_addr_t addr, void *data, bus_size_t size)
+{
+       struct aplefuse_softc *sc = cookie;
+       uint8_t *p = data;
+       uint32_t value;
+       uint8_t buf[4];
+       int offset;
+
+       if (addr > sc->sc_ios || size > sc->sc_ios - addr)
+               return EINVAL;
+
+       offset = addr & 0x3;
+       addr &= ~0x3;
+       while (size > 0) {
+               value = bus_space_read_4(sc->sc_iot, sc->sc_ioh, addr);
+               htolem32(buf, value);
+               memcpy(p, &buf[offset], MIN(size, 4 - offset));
+               size -= MIN(size, 4 - offset);
+               p += MIN(size, 4 - offset);
+               addr += 4;
+               offset = 0;
+       }
+
+       return 0;
+}