[src/trunk]: src/sys/arch/arm/amlogic Auto-detect root device on Meson8b

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

details:   https://anonhg.NetBSD.org/src/rev/2a7b706e99bf
branches:  trunk
changeset: 838530:2a7b706e99bf
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Mon Jan 21 16:27:48 2019 +0000

description:
Auto-detect root device on Meson8b

diffstat:

 sys/arch/arm/amlogic/meson_platform.c |  57 +++++++++++++++++++++++++++++++++-
 1 files changed, 54 insertions(+), 3 deletions(-)

diffs (85 lines):

diff -r f8541397bd6d -r 2a7b706e99bf sys/arch/arm/amlogic/meson_platform.c
--- a/sys/arch/arm/amlogic/meson_platform.c     Mon Jan 21 14:29:12 2019 +0000
+++ b/sys/arch/arm/amlogic/meson_platform.c     Mon Jan 21 16:27:48 2019 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: meson_platform.c,v 1.2 2019/01/20 16:02:32 jmcneill Exp $ */
+/* $NetBSD: meson_platform.c,v 1.3 2019/01/21 16:27:48 jmcneill Exp $ */
 
 /*-
  * Copyright (c) 2019 Jared McNeill <jmcneill%invisible.ca@localhost>
@@ -33,7 +33,7 @@
 #include "arml2cc.h"
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: meson_platform.c,v 1.2 2019/01/20 16:02:32 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: meson_platform.c,v 1.3 2019/01/21 16:27:48 jmcneill Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -197,6 +197,57 @@
        }
 }
 
+#if defined(SOC_MESON8B)
+#define        MESON8B_BOOTINFO_REG    0xd901ff04
+static int
+meson8b_get_boot_id(void)
+{
+       static int boot_id = -1;
+       bus_space_tag_t bst = &arm_generic_bs_tag;
+       bus_space_handle_t bsh;
+
+       if (boot_id == -1) {
+               if (bus_space_map(bst, MESON8B_BOOTINFO_REG, 4, 0, &bsh) != 0)
+                       return -1;
+
+               boot_id = (int)bus_space_read_4(bst, bsh, 0);
+
+               bus_space_unmap(bst, bsh, 4);
+       }
+
+       return boot_id;
+}
+
+static void
+meson8b_platform_device_register(device_t self, void *aux)
+{
+       device_t parent = device_parent(self);
+       char *ptr;
+
+       if (device_is_a(self, "ld") &&
+           device_is_a(parent, "sdmmc") &&
+           (device_is_a(device_parent(parent), "mesonsdhc") ||
+            device_is_a(device_parent(parent), "mesonsdio"))) {
+
+               const int boot_id = meson8b_get_boot_id();
+               const bool has_rootdev = get_bootconf_option(boot_args, "root", BOOTOPT_TYPE_STRING, &ptr) != 0;
+
+               if (!has_rootdev) {
+                       char rootarg[64];
+                       snprintf(rootarg, sizeof(rootarg), " root=%sa", device_xname(self));
+
+                       /* Assume that SDIO is used for SD cards and SDHC is used for eMMC */
+                       if (device_is_a(device_parent(parent), "mesonsdhc") && boot_id == 0)
+                               strcat(boot_args, rootarg);
+                       else if (device_is_a(device_parent(parent), "mesonsdio") && boot_id != 0)
+                               strcat(boot_args, rootarg);
+               }
+       }
+                       
+       meson_platform_device_register(self, aux);
+}
+#endif
+
 static u_int
 meson_platform_uart_freq(void)
 {
@@ -386,7 +437,7 @@
        .ap_devmap = meson_platform_devmap,
        .ap_bootstrap = meson8b_platform_bootstrap,
        .ap_init_attach_args = meson_platform_init_attach_args,
-       .ap_device_register = meson_platform_device_register,
+       .ap_device_register = meson8b_platform_device_register,
        .ap_reset = meson_platform_reset,
        .ap_delay = a9tmr_delay,
        .ap_uart_freq = meson_platform_uart_freq,