drivers/reset/reset-scmi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2019-2020 Linaro Limited
   4  */
   5 #include <common.h>
   6 #include <dm.h>
   7 #include <errno.h>
   8 #include <reset-uclass.h>
   9 #include <scmi_agent.h>
  10 #include <scmi_protocols.h>
  11 #include <asm/types.h>
  12
  13 static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
  14 {
  15         struct scmi_rd_reset_in in = {
  16                 .domain_id = rst->id,
  17                 .flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
  18                 .reset_state = 0,
  19         };
  20         struct scmi_rd_reset_out out;
  21         struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
  22                                           SCMI_RESET_DOMAIN_RESET,
  23                                           in, out);
  24         int ret;
  25
  26         ret = devm_scmi_process_msg(rst->dev->parent, &msg);
  27         if (ret)
  28                 return ret;
  29
  30         return scmi_to_linux_errno(out.status);
  31 }
  32
  33 static int scmi_reset_assert(struct reset_ctl *rst)
  34 {
  35         return scmi_reset_set_level(rst, true);
  36 }
  37
  38 static int scmi_reset_deassert(struct reset_ctl *rst)
  39 {
  40         return scmi_reset_set_level(rst, false);
  41 }
  42
  43 static int scmi_reset_request(struct reset_ctl *rst)
  44 {
  45         struct scmi_rd_attr_in in = {
  46                 .domain_id = rst->id,
  47         };
  48         struct scmi_rd_attr_out out;
  49         struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
  50                                           SCMI_RESET_DOMAIN_ATTRIBUTES,
  51                                           in, out);
  52         int ret;
  53
  54         /*
  55          * We don't really care about the attribute, just check
  56          * the reset domain exists.
  57          */
  58         ret = devm_scmi_process_msg(rst->dev->parent, &msg);
  59         if (ret)
  60                 return ret;
  61
  62         return scmi_to_linux_errno(out.status);
  63 }
  64
  65 static int scmi_reset_rfree(struct reset_ctl *rst)
  66 {
  67         return 0;
  68 }
  69
  70 static const struct reset_ops scmi_reset_domain_ops = {
  71         .request        = scmi_reset_request,
  72         .rfree          = scmi_reset_rfree,
  73         .rst_assert     = scmi_reset_assert,
  74         .rst_deassert   = scmi_reset_deassert,
  75 };
  76
  77 U_BOOT_DRIVER(scmi_reset_domain) = {
  78         .name = "scmi_reset_domain",
  79         .id = UCLASS_RESET,
  80         .ops = &scmi_reset_domain_ops,
  81 };