From c18730a60d89ddd809fe232a320a20188747bb8a Mon Sep 17 00:00:00 2001
From: Adam Madsen <adam@ajmadsen.com>
Date: Fri, 13 Nov 2020 17:22:13 -0600
Subject: [PATCH] [amd] common: Map port I/O space (proper way to access
 certain ATOM registers?)

---
 src/amd/common.c   | 20 ++++++++++++-
 src/amd/common.h   |  3 ++
 src/amd/firmware.c | 72 ++++++++++++++++++++++++++++++++++++++++++++--
 src/amd/firmware.h |  1 +
 4 files changed, 93 insertions(+), 3 deletions(-)

diff --git a/src/amd/common.c b/src/amd/common.c
index e9731d7..c9b4fc0 100644
--- a/src/amd/common.c
+++ b/src/amd/common.c
@@ -32,7 +32,7 @@ int amd_common_pre_reset(struct vendor_reset_dev *dev)
 {
   struct amd_vendor_private *priv;
   struct pci_dev *pdev = dev->pdev;
-  int ret;
+  int ret, i;
 
   /* disable bus reset for the card, seems to be an issue with all of em */
   pdev->dev_flags |= PCI_DEV_FLAGS_NO_BUS_RESET;
@@ -58,6 +58,18 @@ int amd_common_pre_reset(struct vendor_reset_dev *dev)
     goto err_free;
   }
 
+  for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
+  {
+    if (pci_resource_flags(pdev, i) & IORESOURCE_IO)
+    {
+      priv->rio_mem_size = pci_resource_len(pdev, i);
+      priv->rio_mem = pci_iomap(pdev, i, priv->rio_mem_size);
+      break;
+    }
+  }
+  if (!priv->rio_mem)
+    pci_warn(pdev, "Could not map I/O\n");
+
   pci_set_power_state(pdev, PCI_D0);
   pci_clear_master(pdev);
   pci_save_state(pdev);
@@ -82,6 +94,12 @@ int amd_common_post_reset(struct vendor_reset_dev *dev)
     priv->mmio = NULL;
   }
 
+  if (priv->rio_mem)
+  {
+    pci_iounmap(pdev, priv->rio_mem);
+    priv->rio_mem = NULL;
+  }
+
   if (priv->saved_state)
   {
     pci_load_and_free_saved_state(pdev, &priv->saved_state);
diff --git a/src/amd/common.h b/src/amd/common.h
index 77e2d14..dd35c22 100644
--- a/src/amd/common.h
+++ b/src/amd/common.h
@@ -108,6 +108,9 @@ struct amd_vendor_private
   resource_size_t mmio_base;
   resource_size_t mmio_size;
   uint32_t __iomem *mmio;
+
+  resource_size_t rio_mem_size;
+  uint32_t __iomem *rio_mem;
 };
 
 static inline struct amd_vendor_private *adev_to_amd_private(struct amd_fake_dev *adev)
diff --git a/src/amd/firmware.c b/src/amd/firmware.c
index c9d7f82..b0049a4 100644
--- a/src/amd/firmware.c
+++ b/src/amd/firmware.c
@@ -26,6 +26,47 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #include "firmware.h"
 
 #define to_adev(info) ((struct amd_fake_dev *)container_of(info, struct amd_fake_dev, card_info))
+#define RREG32_IO(reg) amdgpu_io_rreg(adev, (reg))
+#define WREG32_IO(reg, v) amdgpu_io_wreg(adev, (reg), (v))
+
+/**
+ * amdgpu_io_rreg - read an IO register
+ *
+ * @adev: amdgpu_device pointer
+ * @reg: dword aligned register offset
+ *
+ * Returns the 32 bit value from the offset specified.
+ */
+u32 amdgpu_io_rreg(struct amd_fake_dev *adev, u32 reg)
+{
+  if ((reg * 4) < adev_to_amd_private(adev)->rio_mem_size)
+    return ioread32(adev_to_amd_private(adev)->rio_mem + (reg * 4));
+  else
+  {
+    iowrite32((reg * 4), adev_to_amd_private(adev)->rio_mem + (mmMM_INDEX * 4));
+    return ioread32(adev_to_amd_private(adev)->rio_mem + (mmMM_DATA * 4));
+  }
+}
+
+/**
+ * amdgpu_io_wreg - write to an IO register
+ *
+ * @adev: amdgpu_device pointer
+ * @reg: dword aligned register offset
+ * @v: 32 bit value to write to the register
+ *
+ * Writes the value specified to the offset specified.
+ */
+void amdgpu_io_wreg(struct amd_fake_dev *adev, u32 reg, u32 v)
+{
+  if ((reg * 4) < adev_to_amd_private(adev)->rio_mem_size)
+    iowrite32(v, adev_to_amd_private(adev)->rio_mem + (reg * 4));
+  else
+  {
+    iowrite32((reg * 4), adev_to_amd_private(adev)->rio_mem + (mmMM_INDEX * 4));
+    iowrite32(v, adev_to_amd_private(adev)->rio_mem + (mmMM_DATA * 4));
+  }
+}
 
 static uint32_t null_read(struct card_info *info, uint32_t reg)
 {
@@ -52,6 +93,22 @@ static uint32_t reg_read(struct card_info *info, uint32_t reg)
   return r;
 }
 
+static uint32_t ioreg_read(struct card_info *info, uint32_t reg)
+{
+  struct amd_fake_dev *adev = to_adev(info);
+  uint32_t r;
+
+  r = RREG32_IO(reg);
+  return r;
+}
+
+static void ioreg_write(struct card_info *info, uint32_t reg, uint32_t val)
+{
+  struct amd_fake_dev *adev = to_adev(info);
+
+  WREG32_IO(reg, val);
+}
+
 int atom_bios_init(struct amd_fake_dev *adev)
 {
   struct card_info *info = &adev->card_info;
@@ -59,8 +116,19 @@ int atom_bios_init(struct amd_fake_dev *adev)
   info->mc_read = info->pll_read = null_read;
   info->mc_write = info->pll_write = null_write;
 
-  info->reg_read = info->ioreg_read = reg_read;
-  info->reg_write = info->ioreg_write = reg_write;
+  info->reg_read = reg_read;
+  info->reg_write = reg_write;
+  if (adev_to_amd_private(adev)->rio_mem)
+  {
+    info->ioreg_read = ioreg_read;
+    info->ioreg_write = ioreg_write;
+  }
+  else
+  {
+    pr_warn("vendor-reset: using MMIO to access I/O\n");
+    info->ioreg_read = reg_read;
+    info->ioreg_write = reg_write;
+  }
 
   adev->atom_context = amdgpu_atom_parse(info, adev->bios);
   if (!adev->atom_context)
diff --git a/src/amd/firmware.h b/src/amd/firmware.h
index 10ad0ba..cd0d757 100644
--- a/src/amd/firmware.h
+++ b/src/amd/firmware.h
@@ -20,6 +20,7 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #ifndef __VENDOR_RESET_FIRMWARE_H__
 #define __VENDOR_RESET_FIRMWARE_H__
 
+struct amd_fake_dev;
 int atom_bios_init(struct amd_fake_dev *adev);
 void atom_bios_fini(struct amd_fake_dev *adev);