target/linux/gemini/patches-4.14/0020-soc-Add-SoC-driver-for-Gemini.patch

   1 From b0a88a861b036124ef2d6acfe6dd87cfde63e750 Mon Sep 17 00:00:00 2001
   2 From: Linus Walleij <linus.walleij@linaro.org>
   3 Date: Fri, 22 Dec 2017 00:19:08 +0100
   4 Subject: [PATCH 20/31] soc: Add SoC driver for Gemini
   5
   6 This adds an SoC driver for the Gemini. Currently there
   7 is only one thing not fitting into any other framework,
   8 and that is the bus arbitration setting.
   9
  10 All Gemini vendor trees seem to be setting this register to
  11 exactly the same arbitration so we just add a small code
  12 snippet to do this at subsys_init() time before any other
  13 drivers kick in.
  14
  15 Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
  16 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
  17 ---
  18  drivers/soc/Makefile            |  1 +
  19  drivers/soc/gemini/Makefile     |  2 ++
  20  drivers/soc/gemini/soc-gemini.c | 71 +++++++++++++++++++++++++++++++++++++++++
  21  3 files changed, 74 insertions(+)
  22  create mode 100644 drivers/soc/gemini/Makefile
  23  create mode 100644 drivers/soc/gemini/soc-gemini.c
  24
  25 --- a/drivers/soc/Makefile
  26 +++ b/drivers/soc/Makefile
  27 @@ -9,6 +9,7 @@ obj-y                           += bcm/
  28  obj-$(CONFIG_ARCH_DOVE)                += dove/
  29  obj-$(CONFIG_MACH_DOVE)                += dove/
  30  obj-y                          += fsl/
  31 +obj-$(CONFIG_ARCH_GEMINI)      += gemini/
  32  obj-$(CONFIG_ARCH_MXC)         += imx/
  33  obj-$(CONFIG_SOC_XWAY)         += lantiq/
  34  obj-$(CONFIG_ARCH_MEDIATEK)    += mediatek/
  35 --- /dev/null
  36 +++ b/drivers/soc/gemini/Makefile
  37 @@ -0,0 +1,2 @@
  38 +# SPDX-License-Identifier: GPL-2.0
  39 +obj-y  += soc-gemini.o
  40 --- /dev/null
  41 +++ b/drivers/soc/gemini/soc-gemini.c
  42 @@ -0,0 +1,71 @@
  43 +// SPDX-License-Identifier: GPL-2.0
  44 +/*
  45 + * Copyright (C) 2017 Linaro Ltd.
  46 + *
  47 + * Author: Linus Walleij <linus.walleij@linaro.org>
  48 + *
  49 + * This program is free software; you can redistribute it and/or modify
  50 + * it under the terms of the GNU General Public License version 2, as
  51 + * published by the Free Software Foundation.
  52 + *
  53 + */
  54 +#include <linux/init.h>
  55 +#include <linux/kernel.h>
  56 +#include <linux/mfd/syscon.h>
  57 +#include <linux/regmap.h>
  58 +#include <linux/of.h>
  59 +
  60 +#define GLOBAL_WORD_ID                         0x00
  61 +#define GEMINI_GLOBAL_ARB1_CTRL                        0x2c
  62 +#define GEMINI_ARB1_BURST_MASK                 GENMASK(21, 16)
  63 +#define GEMINI_ARB1_BURST_SHIFT                        16
  64 +/* These all define the priority on the BUS2 backplane */
  65 +#define GEMINI_ARB1_PRIO_MASK                  GENMASK(9, 0)
  66 +#define GEMINI_ARB1_DMAC_HIGH_PRIO             BIT(0)
  67 +#define GEMINI_ARB1_IDE_HIGH_PRIO              BIT(1)
  68 +#define GEMINI_ARB1_RAID_HIGH_PRIO             BIT(2)
  69 +#define GEMINI_ARB1_SECURITY_HIGH_PRIO         BIT(3)
  70 +#define GEMINI_ARB1_GMAC0_HIGH_PRIO            BIT(4)
  71 +#define GEMINI_ARB1_GMAC1_HIGH_PRIO            BIT(5)
  72 +#define GEMINI_ARB1_USB0_HIGH_PRIO             BIT(6)
  73 +#define GEMINI_ARB1_USB1_HIGH_PRIO             BIT(7)
  74 +#define GEMINI_ARB1_PCI_HIGH_PRIO              BIT(8)
  75 +#define GEMINI_ARB1_TVE_HIGH_PRIO              BIT(9)
  76 +
  77 +#define GEMINI_DEFAULT_BURST_SIZE              0x20
  78 +#define GEMINI_DEFAULT_PRIO                    (GEMINI_ARB1_GMAC0_HIGH_PRIO | \
  79 +                                                GEMINI_ARB1_GMAC1_HIGH_PRIO)
  80 +
  81 +static int __init gemini_soc_init(void)
  82 +{
  83 +       struct regmap *map;
  84 +       u32 rev;
  85 +       u32 val;
  86 +       int ret;
  87 +
  88 +       /* Multiplatform guard, only proceed on Gemini */
  89 +       if (!of_machine_is_compatible("cortina,gemini"))
  90 +               return 0;
  91 +
  92 +       map = syscon_regmap_lookup_by_compatible("cortina,gemini-syscon");
  93 +       if (IS_ERR(map))
  94 +               return PTR_ERR(map);
  95 +       ret = regmap_read(map, GLOBAL_WORD_ID, &rev);
  96 +       if (ret)
  97 +               return ret;
  98 +
  99 +       val = (GEMINI_DEFAULT_BURST_SIZE << GEMINI_ARB1_BURST_SHIFT) |
 100 +               GEMINI_DEFAULT_PRIO;
 101 +
 102 +       /* Set up system arbitration */
 103 +       regmap_update_bits(map,
 104 +                          GEMINI_GLOBAL_ARB1_CTRL,
 105 +                          GEMINI_ARB1_BURST_MASK | GEMINI_ARB1_PRIO_MASK,
 106 +                          val);
 107 +
 108 +       pr_info("Gemini SoC %04x revision %02x, set arbitration %08x\n",
 109 +               rev >> 8, rev & 0xff, val);
 110 +
 111 +       return 0;
 112 +}
 113 +subsys_initcall(gemini_soc_init);