qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
	"Jonathan Cameron" <Jonathan.Cameron@huawei.com>,
	"Fan Ni" <fan.ni@samsung.com>,
	"Philippe Mathieu-Daudé" <philmd@linaro.org>
Subject: [PULL 47/63] hw/cxl: Fix and use same calculation for HDM decoder block size everywhere
Date: Wed, 4 Oct 2023 04:45:42 -0400	[thread overview]
Message-ID: <1fa7342c24fe57b100e0b87ad30113ed65e5eaf1.1696408966.git.mst@redhat.com> (raw)
In-Reply-To: <cover.1696408966.git.mst@redhat.com>

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

In order to avoid having the size of the per HDM decoder register block
repeated in lots of places, create the register definitions for HDM
decoder 1 and use the offset between the first registers in HDM decoder 0 and
HDM decoder 1 to establish the offset.

Calculate in each function as this is more obvious and leads to shorter
line lengths than a single #define which would need a long name
to be specific enough.

Note that the code currently only supports one decoder, so the bugs this
fixes don't actually affect anything.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
--
v3:
New patch to separate this out from the addition of HDM decoders.
Message-Id: <20230913132523.29780-4-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 include/hw/cxl/cxl_component.h |  2 ++
 hw/cxl/cxl-component-utils.c   | 19 +++++++++++--------
 hw/cxl/cxl-host.c              |  4 +++-
 hw/mem/cxl_type3.c             | 24 +++++++++++++++---------
 4 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/include/hw/cxl/cxl_component.h b/include/hw/cxl/cxl_component.h
index ef9e033919..7c864d2044 100644
--- a/include/hw/cxl/cxl_component.h
+++ b/include/hw/cxl/cxl_component.h
@@ -148,6 +148,8 @@ REG32(CXL_HDM_DECODER_GLOBAL_CONTROL, CXL_HDM_REGISTERS_OFFSET + 4)
     FIELD(CXL_HDM_DECODER_GLOBAL_CONTROL, HDM_DECODER_ENABLE, 1, 1)
 
 HDM_DECODER_INIT(0);
+/* Only used for HDM decoder registers block address increment */
+HDM_DECODER_INIT(1);
 
 /* 8.2.5.13 - CXL Extended Security Capability Structure (Root complex only) */
 #define EXTSEC_ENTRY_MAX        256
diff --git a/hw/cxl/cxl-component-utils.c b/hw/cxl/cxl-component-utils.c
index 5f38f2016f..c0630ba5c1 100644
--- a/hw/cxl/cxl-component-utils.c
+++ b/hw/cxl/cxl-component-utils.c
@@ -210,6 +210,7 @@ static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
                             enum reg_type type)
 {
     int decoder_count = 1;
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     int i;
 
     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, DECODER_COUNT,
@@ -222,19 +223,21 @@ static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
                      HDM_DECODER_ENABLE, 0);
     write_msk[R_CXL_HDM_DECODER_GLOBAL_CONTROL] = 0x3;
     for (i = 0; i < decoder_count; i++) {
-        write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * 0x20] = 0xf0000000;
-        write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * 0x20] = 0xffffffff;
-        write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * 0x20] = 0xf0000000;
-        write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * 0x20] = 0xffffffff;
-        write_msk[R_CXL_HDM_DECODER0_CTRL + i * 0x20] = 0x13ff;
+        write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc] = 0xf0000000;
+        write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc] = 0xf0000000;
+        write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_CTRL + i * hdm_inc] = 0x13ff;
         if (type == CXL2_DEVICE ||
             type == CXL2_TYPE3_DEVICE ||
             type == CXL2_LOGICAL_DEVICE) {
-            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xf0000000;
+            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
+                0xf0000000;
         } else {
-            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xffffffff;
+            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
+                0xffffffff;
         }
-        write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * 0x20] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * hdm_inc] = 0xffffffff;
     }
 }
 
diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
index f0920da956..73c5426476 100644
--- a/hw/cxl/cxl-host.c
+++ b/hw/cxl/cxl-host.c
@@ -101,12 +101,14 @@ void cxl_fmws_link_targets(CXLState *cxl_state, Error **errp)
 static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
                                 uint8_t *target)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     uint32_t ctrl;
     uint32_t ig_enc;
     uint32_t iw_enc;
     uint32_t target_idx;
+    int i = 0;
 
-    ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL];
+    ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL + i * hdm_inc];
     if (!FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
         return false;
     }
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 4cdcb3f7e7..9f3022189b 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -388,34 +388,36 @@ static void build_dvsecs(CXLType3Dev *ct3d)
 
 static void hdm_decoder_commit(CXLType3Dev *ct3d, int which)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     ComponentRegisters *cregs = &ct3d->cxl_cstate.crb;
     uint32_t *cache_mem = cregs->cache_mem_registers;
     uint32_t ctrl;
 
     assert(which == 0);
 
-    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL);
+    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc);
     /* TODO: Sanity checks that the decoder is possible */
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0);
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 1);
 
-    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl);
+    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc, ctrl);
 }
 
 static void hdm_decoder_uncommit(CXLType3Dev *ct3d, int which)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     ComponentRegisters *cregs = &ct3d->cxl_cstate.crb;
     uint32_t *cache_mem = cregs->cache_mem_registers;
     uint32_t ctrl;
 
     assert(which == 0);
 
-    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL);
+    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc);
 
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0);
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 0);
 
-    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl);
+    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc, ctrl);
 }
 
 static int ct3d_qmp_uncor_err_to_cxl(CxlUncorErrorType qmp_err)
@@ -772,26 +774,30 @@ static void ct3_exit(PCIDevice *pci_dev)
 /* TODO: Support multiple HDM decoders and DPA skip */
 static bool cxl_type3_dpa(CXLType3Dev *ct3d, hwaddr host_addr, uint64_t *dpa)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     uint32_t *cache_mem = ct3d->cxl_cstate.crb.cache_mem_registers;
     uint64_t decoder_base, decoder_size, hpa_offset;
     uint32_t hdm0_ctrl;
     int ig, iw;
+    int i = 0;
 
-    decoder_base = (((uint64_t)cache_mem[R_CXL_HDM_DECODER0_BASE_HI] << 32) |
-                    cache_mem[R_CXL_HDM_DECODER0_BASE_LO]);
+    decoder_base =
+        (((uint64_t)cache_mem[R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc] << 32) |
+                    cache_mem[R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc]);
     if ((uint64_t)host_addr < decoder_base) {
         return false;
     }
 
     hpa_offset = (uint64_t)host_addr - decoder_base;
 
-    decoder_size = ((uint64_t)cache_mem[R_CXL_HDM_DECODER0_SIZE_HI] << 32) |
-        cache_mem[R_CXL_HDM_DECODER0_SIZE_LO];
+    decoder_size =
+        ((uint64_t)cache_mem[R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc] << 32) |
+        cache_mem[R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc];
     if (hpa_offset >= decoder_size) {
         return false;
     }
 
-    hdm0_ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL];
+    hdm0_ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL + i * hdm_inc];
     iw = FIELD_EX32(hdm0_ctrl, CXL_HDM_DECODER0_CTRL, IW);
     ig = FIELD_EX32(hdm0_ctrl, CXL_HDM_DECODER0_CTRL, IG);
 
-- 
MST



  parent reply	other threads:[~2023-10-04  8:50 UTC|newest]

Thread overview: 99+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-04  8:43 [PULL 00/63] virtio,pci: features, cleanups Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 01/63] pci: SLT must be RO Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 02/63] hw/virtio: Propagate page_mask to vhost_vdpa_listener_skipped_section() Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 03/63] hw/virtio: Propagate page_mask to vhost_vdpa_section_end() Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 04/63] hw/virtio/vhost-vdpa: Inline TARGET_PAGE_ALIGN() macro Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 05/63] hw/virtio/vhost-vdpa: Use target-agnostic qemu_target_page_mask() Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 06/63] hw/virtio: Build vhost-vdpa.o once Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 07/63] hw/virtio/meson: Rename softmmu_virtio_ss[] -> system_virtio_ss[] Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 08/63] virtio: add vhost-user-base and a generic vhost-user-device Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 09/63] hw/virtio: add config support to vhost-user-device Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 10/63] virtio-net: do not reset vlan filtering at set_features Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 11/63] virtio-net: Expose MAX_VLAN Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 12/63] vdpa: Restore vlan filtering state Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 13/63] vdpa: Allow VIRTIO_NET_F_CTRL_VLAN in SVQ Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 14/63] virtio: don't zero out memory region cache for indirect descriptors Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 15/63] vdpa: use first queue SVQ state for CVQ default Michael S. Tsirkin
2023-10-04  8:43 ` [PULL 16/63] vdpa: export vhost_vdpa_set_vring_ready Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 17/63] vdpa: rename vhost_vdpa_net_load to vhost_vdpa_net_cvq_load Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 18/63] vdpa: move vhost_vdpa_set_vring_ready to the caller Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 19/63] vdpa: remove net cvq migration blocker Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 20/63] vhost: Add count argument to vhost_svq_poll() Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 21/63] qmp: remove virtio_list, search QOM tree instead Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 22/63] qmp: update virtio feature maps, vhost-user-gpio introspection Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 23/63] vhost-user: move VhostUserProtocolFeature definition to header file Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 24/63] vhost-user: strip superfluous whitespace Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 25/63] vhost-user: tighten "reply_supported" scope in "set_vring_addr" Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 26/63] vhost-user: factor out "vhost_user_write_sync" Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 27/63] vhost-user: flatten "enforce_reply" into "vhost_user_write_sync" Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 28/63] vhost-user: hoist "write_sync", "get_features", "get_u64" Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 29/63] vhost-user: allow "vhost_set_vring" to wait for a reply Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 30/63] vhost-user: call VHOST_USER_SET_VRING_ENABLE synchronously Michael S. Tsirkin
2023-10-04 10:11   ` Laszlo Ersek
2023-10-04 12:53     ` Michael S. Tsirkin
2023-10-04 13:28       ` Laszlo Ersek
2023-10-04  8:44 ` [PULL 31/63] hw/isa/ich9: Add comment on imperfect emulation of PIC vs. I/O APIC routing Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 32/63] tests/acpi: Allow update of DSDT.cxl Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 33/63] hw/cxl: Add QTG _DSM support for ACPI0017 device Michael S. Tsirkin
2023-10-04 17:46   ` Thomas Huth
2023-10-04 22:14     ` Michael S. Tsirkin
2023-10-04 23:09       ` [PATCH v3] " Dave Jiang
2023-10-05  3:36         ` Michael S. Tsirkin
2023-10-05 16:11           ` Dave Jiang
2023-10-05 16:32             ` Michael S. Tsirkin
2023-10-06 12:09               ` Jonathan Cameron via
2023-10-06 12:09                 ` Jonathan Cameron
2023-10-06 17:50                 ` Dan Williams
2023-10-06 22:15                   ` [PATCH v4] " Dave Jiang
2023-10-09 15:47                     ` Jonathan Cameron via
2023-10-09 15:47                       ` Jonathan Cameron
2023-10-09 16:06                       ` Dave Jiang
2023-10-09 15:44                   ` [PATCH v3] " Jonathan Cameron via
2023-10-09 15:44                     ` Jonathan Cameron
2023-10-07 21:17                 ` Michael S. Tsirkin
2023-10-09 15:40                   ` Jonathan Cameron via
2023-10-09 15:40                     ` Jonathan Cameron
2023-10-05 17:00             ` Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 34/63] tests/acpi: Update DSDT.cxl with QTG DSM Michael S. Tsirkin
2023-10-04  8:44 ` [PULL 35/63] hw/i386/acpi-build: Use pc_madt_cpu_entry() directly Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 36/63] hw/acpi/cpu: Have build_cpus_aml() take a build_madt_cpu_fn callback Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 37/63] hw/acpi/acpi_dev_interface: Remove now unused madt_cpu virtual method Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 38/63] hw/acpi/acpi_dev_interface: Remove now unused #include "hw/boards.h" Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 39/63] hw/i386: Remove now redundant TYPE_ACPI_GED_X86 Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 40/63] hw/i386/acpi-build: Determine SMI command port just once Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 41/63] hw/acpi: Trace GPE access in all device models, not just PIIX4 Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 42/63] hw/acpi/core: Trace enable and status registers of GPE separately Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 43/63] vdpa: fix gcc cvq_isolated uninitialized variable warning Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 44/63] vdpa net: zero vhost_vdpa iova_tree pointer at cleanup Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 45/63] hw/cxl: Push cxl_decoder_count_enc() and cxl_decode_ig() into .c Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 46/63] hw/cxl: Add utility functions decoder interleave ways and target count Michael S. Tsirkin
2023-10-04  8:45 ` Michael S. Tsirkin [this message]
2023-10-04  8:45 ` [PULL 48/63] hw/cxl: Support 4 HDM decoders at all levels of topology Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 49/63] hw/pci-bridge/cxl-upstream: Add serial number extended capability support Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 50/63] vdpa net: fix error message setting virtio status Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 51/63] vdpa net: stop probing if cannot set features Michael S. Tsirkin
2023-10-04  8:45 ` [PULL 52/63] vdpa net: follow VirtIO initialization properly at cvq isolation probing Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 53/63] amd_iommu: Fix APIC address check Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 54/63] hw/i386/pc: improve physical address space bound check for 32-bit x86 systems Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 55/63] pcie_sriov: unregister_vfs(): fix error path Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 56/63] libvhost-user.c: add assertion to vu_message_read_default Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 57/63] virtio: use shadow_avail_idx while checking number of heads Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 58/63] virtio: remove unnecessary thread fence while reading next descriptor Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 59/63] virtio: remove unused next argument from virtqueue_split_read_next_desc() Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 60/63] util/uuid: add a hash function Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 61/63] hw/display: introduce virtio-dmabuf Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 62/63] vhost-user: add shared_object msg Michael S. Tsirkin
2023-10-04  8:46 ` [PULL 63/63] libvhost-user: handle " Michael S. Tsirkin
2023-10-04  8:54 ` [PULL 00/63] virtio,pci: features, cleanups Philippe Mathieu-Daudé
2023-10-04  9:08   ` Michael S. Tsirkin
2023-10-04  8:58 ` Michael S. Tsirkin
2023-10-04 16:26 ` Michael S. Tsirkin
2023-10-04 16:50 ` Stefan Hajnoczi
2023-10-04 17:04   ` Michael S. Tsirkin
2023-10-04 17:40     ` Thomas Huth
2023-10-04 22:23       ` Michael S. Tsirkin
2023-10-05  6:10         ` Thomas Huth
2023-10-04 18:23     ` Stefan Hajnoczi
2023-10-04 17:20   ` Michael S. Tsirkin
2023-10-04 18:29     ` Stefan Hajnoczi
2023-10-04 22:16       ` Michael S. Tsirkin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1fa7342c24fe57b100e0b87ad30113ed65e5eaf1.1696408966.git.mst@redhat.com \
    --to=mst@redhat.com \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=fan.ni@samsung.com \
    --cc=peter.maydell@linaro.org \
    --cc=philmd@linaro.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).