LXR linux/drivers/bus/fsl-mc/fsl-mc-msi.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Freescale Management Complex (MC) bus driver MSI support
   4 *
   5 * Copyright (C) 2015-2016 Freescale Semiconductor, Inc.
   6 * Author: German Rivera <German.Rivera@freescale.com>
   7 *
   8 */
   9
  10#include <linux/of_device.h>
  11#include <linux/of_address.h>
  12#include <linux/of_irq.h>
  13#include <linux/irq.h>
  14#include <linux/irqdomain.h>
  15#include <linux/msi.h>
  16#include <linux/acpi_iort.h>
  17
  18#include "fsl-mc-private.h"
  19
  20#ifdef GENERIC_MSI_DOMAIN_OPS
  21/*
  22 * Generate a unique ID identifying the interrupt (only used within the MSI
  23 * irqdomain.  Combine the icid with the interrupt index.
  24 */
  25static irq_hw_number_t fsl_mc_domain_calc_hwirq(struct fsl_mc_device *dev,
  26                                                struct msi_desc *desc)
  27{
  28        /*
  29         * Make the base hwirq value for ICID*10000 so it is readable
  30         * as a decimal value in /proc/interrupts.
  31         */
  32        return (irq_hw_number_t)(desc->msi_index + (dev->icid * 10000));
  33}
  34
  35static void fsl_mc_msi_set_desc(msi_alloc_info_t *arg,
  36                                struct msi_desc *desc)
  37{
  38        arg->desc = desc;
  39        arg->hwirq = fsl_mc_domain_calc_hwirq(to_fsl_mc_device(desc->dev),
  40                                              desc);
  41}
  42#else
  43#define fsl_mc_msi_set_desc NULL
  44#endif
  45
  46static void fsl_mc_msi_update_dom_ops(struct msi_domain_info *info)
  47{
  48        struct msi_domain_ops *ops = info->ops;
  49
  50        if (!ops)
  51                return;
  52
  53        /*
  54         * set_desc should not be set by the caller
  55         */
  56        if (!ops->set_desc)
  57                ops->set_desc = fsl_mc_msi_set_desc;
  58}
  59
  60static void __fsl_mc_msi_write_msg(struct fsl_mc_device *mc_bus_dev,
  61                                   struct fsl_mc_device_irq *mc_dev_irq,
  62                                   struct msi_desc *msi_desc)
  63{
  64        int error;
  65        struct fsl_mc_device *owner_mc_dev = mc_dev_irq->mc_dev;
  66        struct dprc_irq_cfg irq_cfg;
  67
  68        /*
  69         * msi_desc->msg.address is 0x0 when this function is invoked in
  70         * the free_irq() code path. In this case, for the MC, we don't
  71         * really need to "unprogram" the MSI, so we just return.
  72         */
  73        if (msi_desc->msg.address_lo == 0x0 && msi_desc->msg.address_hi == 0x0)
  74                return;
  75
  76        if (!owner_mc_dev)
  77                return;
  78
  79        irq_cfg.paddr = ((u64)msi_desc->msg.address_hi << 32) |
  80                        msi_desc->msg.address_lo;
  81        irq_cfg.val = msi_desc->msg.data;
  82        irq_cfg.irq_num = msi_desc->irq;
  83
  84        if (owner_mc_dev == mc_bus_dev) {
  85                /*
  86                 * IRQ is for the mc_bus_dev's DPRC itself
  87                 */
  88                error = dprc_set_irq(mc_bus_dev->mc_io,
  89                                     MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
  90                                     mc_bus_dev->mc_handle,
  91                                     mc_dev_irq->dev_irq_index,
  92                                     &irq_cfg);
  93                if (error < 0) {
  94                        dev_err(&owner_mc_dev->dev,
  95                                "dprc_set_irq() failed: %d\n", error);
  96                }
  97        } else {
  98                /*
  99                 * IRQ is for for a child device of mc_bus_dev
 100                 */
 101                error = dprc_set_obj_irq(mc_bus_dev->mc_io,
 102                                         MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
 103                                         mc_bus_dev->mc_handle,
 104                                         owner_mc_dev->obj_desc.type,
 105                                         owner_mc_dev->obj_desc.id,
 106                                         mc_dev_irq->dev_irq_index,
 107                                         &irq_cfg);
 108                if (error < 0) {
 109                        dev_err(&owner_mc_dev->dev,
 110                                "dprc_obj_set_irq() failed: %d\n", error);
 111                }
 112        }
 113}
 114
 115/*
 116 * NOTE: This function is invoked with interrupts disabled
 117 */
 118static void fsl_mc_msi_write_msg(struct irq_data *irq_data,
 119                                 struct msi_msg *msg)
 120{
 121        struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data);
 122        struct fsl_mc_device *mc_bus_dev = to_fsl_mc_device(msi_desc->dev);
 123        struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 124        struct fsl_mc_device_irq *mc_dev_irq =
 125                &mc_bus->irq_resources[msi_desc->msi_index];
 126
 127        msi_desc->msg = *msg;
 128
 129        /*
 130         * Program the MSI (paddr, value) pair in the device:
 131         */
 132        __fsl_mc_msi_write_msg(mc_bus_dev, mc_dev_irq, msi_desc);
 133}
 134
 135static void fsl_mc_msi_update_chip_ops(struct msi_domain_info *info)
 136{
 137        struct irq_chip *chip = info->chip;
 138
 139        if (!chip)
 140                return;
 141
 142        /*
 143         * irq_write_msi_msg should not be set by the caller
 144         */
 145        if (!chip->irq_write_msi_msg)
 146                chip->irq_write_msi_msg = fsl_mc_msi_write_msg;
 147}
 148
 149/**
 150 * fsl_mc_msi_create_irq_domain - Create a fsl-mc MSI interrupt domain
 151 * @fwnode:     Optional firmware node of the interrupt controller
 152 * @info:       MSI domain info
 153 * @parent:     Parent irq domain
 154 *
 155 * Updates the domain and chip ops and creates a fsl-mc MSI
 156 * interrupt domain.
 157 *
 158 * Returns:
 159 * A domain pointer or NULL in case of failure.
 160 */
 161struct irq_domain *fsl_mc_msi_create_irq_domain(struct fwnode_handle *fwnode,
 162                                                struct msi_domain_info *info,
 163                                                struct irq_domain *parent)
 164{
 165        struct irq_domain *domain;
 166
 167        if (WARN_ON((info->flags & MSI_FLAG_LEVEL_CAPABLE)))
 168                info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
 169        if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
 170                fsl_mc_msi_update_dom_ops(info);
 171        if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
 172                fsl_mc_msi_update_chip_ops(info);
 173        info->flags |= MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | MSI_FLAG_FREE_MSI_DESCS;
 174
 175        domain = msi_create_irq_domain(fwnode, info, parent);
 176        if (domain)
 177                irq_domain_update_bus_token(domain, DOMAIN_BUS_FSL_MC_MSI);
 178
 179        return domain;
 180}
 181
 182struct irq_domain *fsl_mc_find_msi_domain(struct device *dev)
 183{
 184        struct device *root_dprc_dev;
 185        struct device *bus_dev;
 186        struct irq_domain *msi_domain;
 187        struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
 188
 189        fsl_mc_get_root_dprc(dev, &root_dprc_dev);
 190        bus_dev = root_dprc_dev->parent;
 191
 192        if (bus_dev->of_node) {
 193                msi_domain = of_msi_map_get_device_domain(dev,
 194                                                  mc_dev->icid,
 195                                                  DOMAIN_BUS_FSL_MC_MSI);
 196
 197                /*
 198                 * if the msi-map property is missing assume that all the
 199                 * child containers inherit the domain from the parent
 200                 */
 201                if (!msi_domain)
 202
 203                        msi_domain = of_msi_get_domain(bus_dev,
 204                                                bus_dev->of_node,
 205                                                DOMAIN_BUS_FSL_MC_MSI);
 206        } else {
 207                msi_domain = iort_get_device_domain(dev, mc_dev->icid,
 208                                                    DOMAIN_BUS_FSL_MC_MSI);
 209        }
 210
 211        return msi_domain;
 212}
 213
 214int fsl_mc_msi_domain_alloc_irqs(struct device *dev,  unsigned int irq_count)
 215{
 216        struct irq_domain *msi_domain;
 217        int error;
 218
 219        msi_domain = dev_get_msi_domain(dev);
 220        if (!msi_domain)
 221                return -EINVAL;
 222
 223        error = msi_setup_device_data(dev);
 224        if (error)
 225                return error;
 226
 227        if (msi_first_desc(dev, MSI_DESC_ALL))
 228                return -EINVAL;
 229
 230        /*
 231         * NOTE: Calling this function will trigger the invocation of the
 232         * its_fsl_mc_msi_prepare() callback
 233         */
 234        error = msi_domain_alloc_irqs(msi_domain, dev, irq_count);
 235
 236        if (error)
 237                dev_err(dev, "Failed to allocate IRQs\n");
 238        return error;
 239}
 240
 241void fsl_mc_msi_domain_free_irqs(struct device *dev)
 242{
 243        struct irq_domain *msi_domain;
 244
 245        msi_domain = dev_get_msi_domain(dev);
 246        if (!msi_domain)
 247                return;
 248
 249        msi_domain_free_irqs(msi_domain, dev);
 250}
 251