According to PCI SIG ECN, calling the _DSM firmware method for a given
CPU_UID returns the steering tags for different types of memory
(volatile, non-volatile). These tags are supposed to be used in ST
table entry for optimal results.
Co-developed-by: Eric Van Tassell <Eric.VanTassell@amd.com>
Signed-off-by: Eric Van Tassell <Eric.VanTassell@amd.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
---
drivers/pci/pcie/tph.c | 103 +++++++++++++++++++++++++++++++++++++++-
include/linux/pci-tph.h | 34 +++++++++++++
2 files changed, 136 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/tph.c b/drivers/pci/pcie/tph.c
index 50451a0a32ff..b9d61e1cfd88 100644
--- a/drivers/pci/pcie/tph.c
+++ b/drivers/pci/pcie/tph.c
@@ -158,6 +158,98 @@ static int tph_get_table_location(struct pci_dev *dev, u8 *loc_out)
return 0;
}
+static u16 tph_extract_tag(enum tph_mem_type mem_type, u8 req_type,
+ union st_info *st_tag)
+{
+ switch (req_type) {
+ case PCI_TPH_REQ_TPH_ONLY: /* 8 bit tags */
+ switch (mem_type) {
+ case TPH_MEM_TYPE_VM:
+ if (st_tag->vm_st_valid)
+ return st_tag->vm_st;
+ break;
+ case TPH_MEM_TYPE_PM:
+ if (st_tag->pm_st_valid)
+ return st_tag->pm_st;
+ break;
+ }
+ break;
+ case PCI_TPH_REQ_EXT_TPH: /* 16 bit tags */
+ switch (mem_type) {
+ case TPH_MEM_TYPE_VM:
+ if (st_tag->vm_xst_valid)
+ return st_tag->vm_xst;
+ break;
+ case TPH_MEM_TYPE_PM:
+ if (st_tag->pm_xst_valid)
+ return st_tag->pm_xst;
+ break;
+ }
+ break;
+ default:
+ pr_err("invalid steering tag in ACPI _DSM\n");
+ return 0;
+ }
+
+ return 0;
+}
+
+#define MIN_ST_DSM_REV 7
+#define ST_DSM_FUNC_INDEX 0xf
+static bool invoke_dsm(acpi_handle handle, u32 cpu_uid, u8 ph,
+ u8 target_type, bool cache_ref_valid,
+ u64 cache_ref, union st_info *st_out)
+{
+ union acpi_object in_obj, in_buf[3], *out_obj;
+
+ in_buf[0].integer.type = ACPI_TYPE_INTEGER;
+ in_buf[0].integer.value = 0; /* 0 => processor cache steering tags */
+
+ in_buf[1].integer.type = ACPI_TYPE_INTEGER;
+ in_buf[1].integer.value = cpu_uid;
+
+ in_buf[2].integer.type = ACPI_TYPE_INTEGER;
+ in_buf[2].integer.value = ph & 3;
+ in_buf[2].integer.value |= (target_type & 1) << 2;
+ in_buf[2].integer.value |= (cache_ref_valid & 1) << 3;
+ in_buf[2].integer.value |= (cache_ref << 32);
+
+ in_obj.type = ACPI_TYPE_PACKAGE;
+ in_obj.package.count = ARRAY_SIZE(in_buf);
+ in_obj.package.elements = in_buf;
+
+ out_obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, MIN_ST_DSM_REV,
+ ST_DSM_FUNC_INDEX, &in_obj);
+
+ if (!out_obj)
+ return false;
+
+ if (out_obj->type != ACPI_TYPE_BUFFER) {
+ pr_err("invalid return type %d from TPH _DSM\n",
+ out_obj->type);
+ ACPI_FREE(out_obj);
+ return false;
+ }
+
+ st_out->value = *((u64 *)(out_obj->buffer.pointer));
+
+ ACPI_FREE(out_obj);
+
+ return true;
+}
+
+static acpi_handle root_complex_acpi_handle(struct pci_dev *dev)
+{
+ struct pci_dev *root_port;
+
+ root_port = pcie_find_root_port(dev);
+
+ if (!root_port || !root_port->bus || !root_port->bus->bridge)
+ return NULL;
+
+ return ACPI_HANDLE(root_port->bus->bridge);
+}
+
static bool msix_nr_in_bounds(struct pci_dev *dev, int msix_nr)
{
u16 tbl_sz;
@@ -423,7 +515,16 @@ bool pcie_tph_get_st(struct pci_dev *dev, unsigned int cpu,
enum tph_mem_type mem_type, u8 req_type,
u16 *tag)
{
- *tag = 0;
+ union st_info info;
+
+ if (!invoke_dsm(root_complex_acpi_handle(dev), cpu, 0, 0, false, 0,
+ &info)) {
+ *tag = 0;
+ return false;
+ }
+
+ *tag = tph_extract_tag(mem_type, req_type, &info);
+ pr_debug("%s: cpu=%d tag=%d\n", __func__, cpu, *tag);
return true;
}
diff --git a/include/linux/pci-tph.h b/include/linux/pci-tph.h
index 42ecd6192e69..ed5299a831cb 100644
--- a/include/linux/pci-tph.h
+++ b/include/linux/pci-tph.h
@@ -14,6 +14,40 @@ enum tph_mem_type {
TPH_MEM_TYPE_PM /* persistent memory type */
};
+/*
+ * The st_info struct defines the steering tag returned by the firmware _DSM
+ * method defined in PCI SIG ECN. The specification is available at:
+ * https://members.pcisig.com/wg/PCI-SIG/document/15470.
+
+ * @vm_st_valid: 8 bit tag for volatile memory is valid
+ * @vm_xst_valid: 16 bit tag for volatile memory is valid
+ * @vm_ignore: 1 => was and will be ignored, 0 => ph should be supplied
+ * @vm_st: 8 bit steering tag for volatile mem
+ * @vm_xst: 16 bit steering tag for volatile mem
+ * @pm_st_valid: 8 bit tag for persistent memory is valid
+ * @pm_xst_valid: 16 bit tag for persistent memory is valid
+ * @pm_ignore: 1 => was and will be ignore, 0 => ph should be supplied
+ * @pm_st: 8 bit steering tag for persistent mem
+ * @pm_xst: 16 bit steering tag for persistent mem
+ */
+union st_info {
+ struct {
+ u64 vm_st_valid:1,
+ vm_xst_valid:1,
+ vm_ph_ignore:1,
+ rsvd1:5,
+ vm_st:8,
+ vm_xst:16,
+ pm_st_valid:1,
+ pm_xst_valid:1,
+ pm_ph_ignore:1,
+ rsvd2:5,
+ pm_st:8,
+ pm_xst:16;
+ };
+ u64 value;
+};
+
#ifdef CONFIG_PCIE_TPH
int pcie_tph_disable(struct pci_dev *dev);
int tph_set_dev_nostmode(struct pci_dev *dev);
--
2.44.0Hi Wei,
kernel test robot noticed the following build errors:
[auto build test ERROR on pci/for-linus]
[also build test ERROR on awilliam-vfio/next linus/master awilliam-vfio/for-linus v6.9-rc7 next-20240509]
[cannot apply to pci/next horms-ipvs/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Wei-Huang/PCI-Introduce-PCIe-TPH-support-framework/20240510-003504
base: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git for-linus
patch link: https://lore.kernel.org/r/20240509162741.1937586-7-wei.huang2%40amd.com
patch subject: [PATCH V1 6/9] PCI/TPH: Retrieve steering tag from ACPI _DSM
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20240510/202405101330.7jDvJ4Jc-lkp@intel.com/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project b910bebc300dafb30569cecc3017b446ea8eafa0)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240510/202405101330.7jDvJ4Jc-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202405101330.7jDvJ4Jc-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from drivers/pci/pcie/tph.c:13:
In file included from include/linux/acpi.h:14:
In file included from include/linux/device.h:32:
In file included from include/linux/device/driver.h:21:
In file included from include/linux/module.h:19:
In file included from include/linux/elf.h:6:
In file included from arch/s390/include/asm/elf.h:173:
In file included from arch/s390/include/asm/mmu_context.h:11:
In file included from arch/s390/include/asm/pgalloc.h:18:
In file included from include/linux/mm.h:2208:
include/linux/vmstat.h:508:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
508 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
509 | item];
| ~~~~
include/linux/vmstat.h:515:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
515 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
516 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
include/linux/vmstat.h:522:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
522 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
include/linux/vmstat.h:527:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
527 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
528 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
include/linux/vmstat.h:536:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
536 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
537 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/pci/pcie/tph.c:17:
In file included from include/linux/msi.h:27:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
547 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
| ^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
| ^
In file included from drivers/pci/pcie/tph.c:17:
In file included from include/linux/msi.h:27:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
| ^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
| ^
In file included from drivers/pci/pcie/tph.c:17:
In file included from include/linux/msi.h:27:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
692 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
700 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
708 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
717 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
726 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
735 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
>> drivers/pci/pcie/tph.c:221:39: error: use of undeclared identifier 'pci_acpi_dsm_guid'
221 | out_obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, MIN_ST_DSM_REV,
| ^
17 warnings and 1 error generated.
vim +/pci_acpi_dsm_guid +221 drivers/pci/pcie/tph.c
196
197 #define MIN_ST_DSM_REV 7
198 #define ST_DSM_FUNC_INDEX 0xf
199 static bool invoke_dsm(acpi_handle handle, u32 cpu_uid, u8 ph,
200 u8 target_type, bool cache_ref_valid,
201 u64 cache_ref, union st_info *st_out)
202 {
203 union acpi_object in_obj, in_buf[3], *out_obj;
204
205 in_buf[0].integer.type = ACPI_TYPE_INTEGER;
206 in_buf[0].integer.value = 0; /* 0 => processor cache steering tags */
207
208 in_buf[1].integer.type = ACPI_TYPE_INTEGER;
209 in_buf[1].integer.value = cpu_uid;
210
211 in_buf[2].integer.type = ACPI_TYPE_INTEGER;
212 in_buf[2].integer.value = ph & 3;
213 in_buf[2].integer.value |= (target_type & 1) << 2;
214 in_buf[2].integer.value |= (cache_ref_valid & 1) << 3;
215 in_buf[2].integer.value |= (cache_ref << 32);
216
217 in_obj.type = ACPI_TYPE_PACKAGE;
218 in_obj.package.count = ARRAY_SIZE(in_buf);
219 in_obj.package.elements = in_buf;
220
> 221 out_obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, MIN_ST_DSM_REV,
222 ST_DSM_FUNC_INDEX, &in_obj);
223
224 if (!out_obj)
225 return false;
226
227 if (out_obj->type != ACPI_TYPE_BUFFER) {
228 pr_err("invalid return type %d from TPH _DSM\n",
229 out_obj->type);
230 ACPI_FREE(out_obj);
231 return false;
232 }
233
234 st_out->value = *((u64 *)(out_obj->buffer.pointer));
235
236 ACPI_FREE(out_obj);
237
238 return true;
239 }
240
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Wei,
kernel test robot noticed the following build errors:
[auto build test ERROR on pci/for-linus]
[also build test ERROR on awilliam-vfio/next linus/master awilliam-vfio/for-linus v6.9-rc7 next-20240509]
[cannot apply to pci/next horms-ipvs/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Wei-Huang/PCI-Introduce-PCIe-TPH-support-framework/20240510-003504
base: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git for-linus
patch link: https://lore.kernel.org/r/20240509162741.1937586-7-wei.huang2%40amd.com
patch subject: [PATCH V1 6/9] PCI/TPH: Retrieve steering tag from ACPI _DSM
config: parisc-randconfig-r081-20240510 (https://download.01.org/0day-ci/archive/20240510/202405101200.FPuliW1p-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240510/202405101200.FPuliW1p-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202405101200.FPuliW1p-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/pci/pcie/tph.c: In function 'tph_msix_table_entry':
drivers/pci/pcie/tph.c:95:22: error: 'struct pci_dev' has no member named 'msix_base'; did you mean 'msix_cap'?
95 | entry = dev->msix_base + msi_index * PCI_MSIX_ENTRY_SIZE;
| ^~~~~~~~~
| msix_cap
drivers/pci/pcie/tph.c: In function 'invoke_dsm':
>> drivers/pci/pcie/tph.c:221:46: error: 'pci_acpi_dsm_guid' undeclared (first use in this function)
221 | out_obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, MIN_ST_DSM_REV,
| ^~~~~~~~~~~~~~~~~
drivers/pci/pcie/tph.c:221:46: note: each undeclared identifier is reported only once for each function it appears in
vim +/pci_acpi_dsm_guid +221 drivers/pci/pcie/tph.c
196
197 #define MIN_ST_DSM_REV 7
198 #define ST_DSM_FUNC_INDEX 0xf
199 static bool invoke_dsm(acpi_handle handle, u32 cpu_uid, u8 ph,
200 u8 target_type, bool cache_ref_valid,
201 u64 cache_ref, union st_info *st_out)
202 {
203 union acpi_object in_obj, in_buf[3], *out_obj;
204
205 in_buf[0].integer.type = ACPI_TYPE_INTEGER;
206 in_buf[0].integer.value = 0; /* 0 => processor cache steering tags */
207
208 in_buf[1].integer.type = ACPI_TYPE_INTEGER;
209 in_buf[1].integer.value = cpu_uid;
210
211 in_buf[2].integer.type = ACPI_TYPE_INTEGER;
212 in_buf[2].integer.value = ph & 3;
213 in_buf[2].integer.value |= (target_type & 1) << 2;
214 in_buf[2].integer.value |= (cache_ref_valid & 1) << 3;
215 in_buf[2].integer.value |= (cache_ref << 32);
216
217 in_obj.type = ACPI_TYPE_PACKAGE;
218 in_obj.package.count = ARRAY_SIZE(in_buf);
219 in_obj.package.elements = in_buf;
220
> 221 out_obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, MIN_ST_DSM_REV,
222 ST_DSM_FUNC_INDEX, &in_obj);
223
224 if (!out_obj)
225 return false;
226
227 if (out_obj->type != ACPI_TYPE_BUFFER) {
228 pr_err("invalid return type %d from TPH _DSM\n",
229 out_obj->type);
230 ACPI_FREE(out_obj);
231 return false;
232 }
233
234 st_out->value = *((u64 *)(out_obj->buffer.pointer));
235
236 ACPI_FREE(out_obj);
237
238 return true;
239 }
240
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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