[PATCH v2 libacpica] Allow read/write to pci config

[Damien Zammit]

---
 debian/patches/acgnu.diff           | 72 ++++++++++++++++++++---
 debian/patches/acpi-init-files.diff | 88 ++++++++++++++++++++++++++++-
 debian/patches/add-makefile.diff    |  4 +-
 3 files changed, 153 insertions(+), 11 deletions(-)

diff --git a/debian/patches/acgnu.diff b/debian/patches/acgnu.diff
index fc59992..e7f396f 100644
--- a/debian/patches/acgnu.diff
+++ b/debian/patches/acgnu.diff
@@ -163,7 +163,7 @@ Add acgnu.h and acgnuex.h
 +#endif                                /* __ACGNU_H__ */
 --- /dev/null
 +++ b/include/acpi/platform/acgnuex.h
-@@ -0,0 +1,256 @@
+@@ -0,0 +1,314 @@
 +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 +
 +#ifndef __ACGNUEX_H__
@@ -181,6 +181,8 @@ Add acgnu.h and acgnuex.h
 +acpi_status ACPI_INIT_FUNCTION acpi_os_initialize(void);
 +acpi_status acpi_os_terminate(void);
 +void acpi_os_printf(const char *format, ...);
++struct pci_device;
++struct pci_device *lookup_pci_dev(struct acpi_pci_id *pci_id);
 +
 +static inline void *acpi_os_allocate(acpi_size size)
 +{
@@ -232,6 +234,7 @@ Add acgnu.h and acgnuex.h
 +#include <stdarg.h>
 +#include <limits.h>
 +#include <hurd.h>
++#include <pciaccess.h>
 +
 +#define ACPI_MAX_TABLES 128
 +
@@ -403,18 +406,73 @@ Add acgnu.h and acgnuex.h
 +
 +static inline acpi_status
 +acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
-+             u64 *value, u32 width)
++             u64 *value, u32 bit_width)
 +{
-+  acpi_os_printf("ACPI: Tried to read pci config\n");
-+  return 1;
++  int i, err = 0;
++  uint8_t buf[8] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
++  struct pci_device *dev;
++  u64 temp = 0;
++  u32 bytes = bit_width / 8;
++  pciaddr_t bytes_read = 0;
++
++  if (bytes > 8)
++    {
++      acpi_os_printf("acpi: Can't read more than 8 pci bytes\n");
++      return 1;
++    }
++
++  dev = lookup_pci_dev(pci_id);
++  if (!dev)
++    return 1;
++
++  pci_device_cfg_read(dev, buf, reg, bytes, &bytes_read);
++  if (bytes_read < bytes)
++    {
++      acpi_os_printf("acpi: pci short read\n");
++      err = 1;
++    }
++
++  /* Read buffer from LE */
++  for (i = 0; i < bytes; i++)
++    temp |= buf[i] << (8 * i);
++
++  *value = temp;
++
++  return err;
 +}
 +
 +static inline acpi_status
 +acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
-+        u64 value, u32 width)
++        u64 value, u32 bit_width)
 +{
-+  acpi_os_printf("ACPI: Tried to write pci config\n");
-+  return 1;
++  int i, err = 0;
++  uint8_t buf[8] = {0};
++  struct pci_device *dev;
++  u32 bytes = bit_width / 8;
++  pciaddr_t bytes_written = 0;
++
++  if (bytes > 8)
++    {
++      acpi_os_printf("acpi: Can't write more than 8 pci bytes\n");
++      return 1;
++    }
++
++  dev = lookup_pci_dev(pci_id);
++  if (!dev)
++    return 1;
++
++  /* Encode value as LE buffer */
++  for (i = 0; i < bytes; i++)
++    buf[i] = (value >> (8 * i)) & 0xff;
++
++  pci_device_cfg_write(dev, buf, reg, bytes, &bytes_written);
++  if (bytes_written < bytes)
++    {
++      acpi_os_printf("acpi: pci short write\n");
++      err = 1;
++    }
++
++  return err;
 +}
 +
 +#endif                                /* __KERNEL__ */
diff --git a/debian/patches/acpi-init-files.diff 
b/debian/patches/acpi-init-files.diff
index b83eafd..e277749 100644
--- a/debian/patches/acpi-init-files.diff
+++ b/debian/patches/acpi-init-files.diff
@@ -1,6 +1,6 @@
 --- /dev/null
 +++ b/acpi_init.c
-@@ -0,0 +1,510 @@
+@@ -0,0 +1,592 @@
 +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 +#include <acpi/acpi.h>
 +
@@ -24,14 +24,21 @@
 +
 +#include <device/device.h>
 +#include <hurd.h>
++#include <pciaccess.h>
 +
 +#define ACPI_MAX_TABLES 128
 +
++#define PCI_CFG1_START 0xcf8
++#define PCI_CFG1_END   0xcff
++
 +extern acpi_status acpi_hw_legacy_sleep(u8 sleep_state);
 +
 +// Lets keep the ACPI tables in this module
 +static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES];
 +
++static struct pci_device **pci_devices;
++static int numdevs = -1;
++
 +struct slots {
 +  uint8_t bus;
 +  uint16_t dev;
@@ -40,6 +47,61 @@
 +  struct slots *next;
 +};
 +
++static int
++pci_init(void)
++{
++  int i;
++  struct pci_device_iterator *dev_iter;
++  struct pci_device *pci_dev;
++  struct pci_device **tmp;
++
++  pci_system_init ();
++
++  numdevs = 0;
++  dev_iter = pci_slot_match_iterator_create (NULL);
++  while ((pci_dev = pci_device_next (dev_iter)) != NULL)
++    numdevs++;
++
++  pci_devices = malloc (sizeof(struct pci_device *));
++  if (pci_devices == NULL)
++    return errno;
++  tmp = pci_devices;
++
++  i = 0;
++  dev_iter = pci_slot_match_iterator_create (NULL);
++  while ((pci_dev = pci_device_next (dev_iter)) != NULL)
++    {
++      if ((tmp = realloc(pci_devices, (i + 1) * sizeof(*tmp))) == NULL)
++        {
++          free(pci_devices);
++          return errno;
++        }
++      pci_devices = tmp;
++      pci_device_probe(pci_dev);
++      pci_devices[i++] = pci_dev;
++    }
++  return 0;
++}
++
++struct pci_device *
++lookup_pci_dev(struct acpi_pci_id *pci_id)
++{
++  int i;
++
++  for (i = 0; i < numdevs; i++)
++    {
++      if ((pci_devices[i]->domain == pci_id->segment)
++       && (pci_devices[i]->bus == pci_id->bus)
++       && (pci_devices[i]->dev == pci_id->device)
++       && (pci_devices[i]->func == pci_id->function))
++        {
++          return pci_devices[i];
++        }
++    }
++    acpi_os_printf("Can't find pci dev %04x:%d:%02x.%d\n", pci_id->segment, 
pci_id->bus, pci_id->device, pci_id->function);
++    return NULL;
++}
++
 +void
 +acpi_ds_dump_method_stack(acpi_status status, ...)
 +//    struct acpi_walk_state *walk_state, union acpi_parse_object *op)
@@ -224,17 +286,37 @@
 +acpi_status
 +acpi_os_initialize(void)
 +{
-+  if (ioperm(0, 0x10000, 1))
++  /* Avoid giving ioperm to the PCI cfg registers
++   * since pci-arbiter controls these
++   */
++
++  /* 0-0xcf7 */
++  if (ioperm(0, PCI_CFG1_START, 1))
 +    {
-+      acpi_os_printf("EPERM on ioperm\n");
++      acpi_os_printf("acpi: EPERM on ioperm 1\n");
 +      return AE_ERROR;
 +    }
++
++  /* 0xd00-0xffff */
++  if (ioperm(PCI_CFG1_END+1, 0x10000 - (PCI_CFG1_END+1), 1))
++    {
++      acpi_os_printf("acpi: EPERM on ioperm 2\n");
++      return AE_ERROR;
++    }
++
++  if (pci_init())
++    {
++      acpi_os_printf("acpi pci_init: Error realloc\n");
++      return AE_ERROR;
++    }
++
 +  return AE_OK;
 +}
 +
 +acpi_status
 +acpi_os_terminate(void)
 +{
++  free(pci_devices);
 +  acpi_os_printf("Bye!\n");
 +  return AE_OK;
 +}
diff --git a/debian/patches/add-makefile.diff b/debian/patches/add-makefile.diff
index da2edc3..a78d8d0 100644
--- a/debian/patches/add-makefile.diff
+++ b/debian/patches/add-makefile.diff
@@ -1,6 +1,6 @@
 --- /dev/null
 +++ b/Makefile
-@@ -0,0 +1,216 @@
+@@ -0,0 +1,218 @@
 +# Copyright (C) 2022 Free Software Foundation, Inc.
 +#
 +# This is free software; you can redistribute it and/or modify
@@ -37,6 +37,8 @@
 +PREFIX ?= /usr/local
 +libdir ?= $(PREFIX)/lib
 +
++LDLIBS = -lpciaccess
++
 +SRCS =        global_state.c          \
 +      acpi_init.c             \
 +      $(BASE)/dsargs.c        \
-- 
2.40.1