4.20-stable patches

added patches:
	media-cx23885-only-reset-dma-on-problematic-cpus.patch

diff --git a/queue-4.20/media-cx23885-only-reset-dma-on-problematic-cpus.patch b/queue-4.20/media-cx23885-only-reset-dma-on-problematic-cpus.patch
new file mode 100644 (file)
index 0000000..e39390c
--- /dev/null
+++ b/queue-4.20/media-cx23885-only-reset-dma-on-problematic-cpus.patch
@@ -0,0 +1,131 @@
+From 4bd46aa0353e022c2401a258e93b107880a66533 Mon Sep 17 00:00:00 2001
+From: Brad Love <brad@nextdimension.cc>
+Date: Wed, 19 Dec 2018 12:07:01 -0500
+Subject: media: cx23885: only reset DMA on problematic CPUs
+
+From: Brad Love <brad@nextdimension.cc>
+
+commit 4bd46aa0353e022c2401a258e93b107880a66533 upstream.
+
+It is reported that commit 95f408bbc4e4 ("media: cx23885: Ryzen DMA
+related RiSC engine stall fixes") caused regresssions with other CPUs.
+
+Ensure that the quirk will be applied only for the CPUs that
+are known to cause problems.
+
+A module option is added for explicit control of the behaviour.
+
+Fixes: 95f408bbc4e4 ("media: cx23885: Ryzen DMA related RiSC engine stall fixes")
+
+Signed-off-by: Brad Love <brad@nextdimension.cc>
+Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/media/pci/cx23885/cx23885-core.c |   55 +++++++++++++++++++++++++++++--
+ drivers/media/pci/cx23885/cx23885.h      |    2 +
+ 2 files changed, 55 insertions(+), 2 deletions(-)
+
+--- a/drivers/media/pci/cx23885/cx23885-core.c
++++ b/drivers/media/pci/cx23885/cx23885-core.c
+@@ -23,6 +23,7 @@
+ #include <linux/moduleparam.h>
+ #include <linux/kmod.h>
+ #include <linux/kernel.h>
++#include <linux/pci.h>
+ #include <linux/slab.h>
+ #include <linux/interrupt.h>
+ #include <linux/delay.h>
+@@ -41,6 +42,18 @@ MODULE_AUTHOR("Steven Toth <stoth@linuxt
+ MODULE_LICENSE("GPL");
+ MODULE_VERSION(CX23885_VERSION);
+ 
++/*
++ * Some platforms have been found to require periodic resetting of the DMA
++ * engine. Ryzen and XEON platforms are known to be affected. The symptom
++ * encountered is "mpeg risc op code error". Only Ryzen platforms employ
++ * this workaround if the option equals 1. The workaround can be explicitly
++ * disabled for all platforms by setting to 0, the workaround can be forced
++ * on for any platform by setting to 2.
++ */
++static unsigned int dma_reset_workaround = 1;
++module_param(dma_reset_workaround, int, 0644);
++MODULE_PARM_DESC(dma_reset_workaround, "periodic RiSC dma engine reset; 0-force disable, 1-driver detect (default), 2-force enable");
++
+ static unsigned int debug;
+ module_param(debug, int, 0644);
+ MODULE_PARM_DESC(debug, "enable debug messages");
+@@ -603,8 +616,13 @@ static void cx23885_risc_disasm(struct c
+ 
+ static void cx23885_clear_bridge_error(struct cx23885_dev *dev)
+ {
+-      uint32_t reg1_val = cx_read(TC_REQ); /* read-only */
+-      uint32_t reg2_val = cx_read(TC_REQ_SET);
++      uint32_t reg1_val, reg2_val;
++
++      if (!dev->need_dma_reset)
++              return;
++
++      reg1_val = cx_read(TC_REQ); /* read-only */
++      reg2_val = cx_read(TC_REQ_SET);
+ 
+       if (reg1_val && reg2_val) {
+               cx_write(TC_REQ, reg1_val);
+@@ -2058,6 +2076,37 @@ void cx23885_gpio_enable(struct cx23885_
+       /* TODO: 23-19 */
+ }
+ 
++static struct {
++      int vendor, dev;
++} const broken_dev_id[] = {
++      /* According with
++       * https://openbenchmarking.org/system/1703021-RI-AMDZEN08075/Ryzen%207%201800X/lspci,
++       * 0x1451 is PCI ID for the IOMMU found on Ryzen
++       */
++      { PCI_VENDOR_ID_AMD, 0x1451 },
++};
++
++static bool cx23885_does_need_dma_reset(void)
++{
++      int i;
++      struct pci_dev *pdev = NULL;
++
++      if (dma_reset_workaround == 0)
++              return false;
++      else if (dma_reset_workaround == 2)
++              return true;
++
++      for (i = 0; i < ARRAY_SIZE(broken_dev_id); i++) {
++              pdev = pci_get_device(broken_dev_id[i].vendor,
++                                    broken_dev_id[i].dev, NULL);
++              if (pdev) {
++                      pci_dev_put(pdev);
++                      return true;
++              }
++      }
++      return false;
++}
++
+ static int cx23885_initdev(struct pci_dev *pci_dev,
+                          const struct pci_device_id *pci_id)
+ {
+@@ -2069,6 +2118,8 @@ static int cx23885_initdev(struct pci_de
+       if (NULL == dev)
+               return -ENOMEM;
+ 
++      dev->need_dma_reset = cx23885_does_need_dma_reset();
++
+       err = v4l2_device_register(&pci_dev->dev, &dev->v4l2_dev);
+       if (err < 0)
+               goto fail_free;
+--- a/drivers/media/pci/cx23885/cx23885.h
++++ b/drivers/media/pci/cx23885/cx23885.h
+@@ -451,6 +451,8 @@ struct cx23885_dev {
+       /* Analog raw audio */
+       struct cx23885_audio_dev   *audio_dev;
+ 
++      /* Does the system require periodic DMA resets? */
++      unsigned int            need_dma_reset:1;
+ };
+ 
+ static inline struct cx23885_dev *to_cx23885(struct v4l2_device *v4l2_dev)

diff --git a/queue-4.20/series b/queue-4.20/series
index 462217d26379c98add6d672cc1a0406bbb0508b5..1d3ccd72142f9c8c99566a533c43a98580adac13 100644 (file)
--- a/queue-4.20/series
+++ b/queue-4.20/series
@@ -14,3 +14,4 @@ mm-hmm-use-devm-semantics-for-hmm_devmem_-add-remove.patch
 mm-hmm-replace-hmm_devmem_pages_create-with-devm_memremap_pages.patch
 mm-hmm-mark-hmm_devmem_-add-add_resource-export_symbol_gpl.patch
 mm-swap-fix-swapoff-with-ksm-pages.patch
+media-cx23885-only-reset-dma-on-problematic-cpus.patch