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-rw-r--r--patches/drivers/mailbox/0001-mailbox-PCC-erroneous-error-message-when-parsing-ACPI-PCCT.patch239
-rw-r--r--patches/drivers/mailbox/acpi-pcct.scc2
2 files changed, 0 insertions, 241 deletions
diff --git a/patches/drivers/mailbox/0001-mailbox-PCC-erroneous-error-message-when-parsing-ACPI-PCCT.patch b/patches/drivers/mailbox/0001-mailbox-PCC-erroneous-error-message-when-parsing-ACPI-PCCT.patch
deleted file mode 100644
index 48cdda2..0000000
--- a/patches/drivers/mailbox/0001-mailbox-PCC-erroneous-error-message-when-parsing-ACPI-PCCT.patch
+++ /dev/null
@@ -1,239 +0,0 @@
1From 8f8027c5f935bf02bdc8806c109ddbb0e402283c Mon Sep 17 00:00:00 2001
2From: Al Stone <ahs3@redhat.com>
3Date: Wed, 16 May 2018 16:01:41 -0600
4Subject: [PATCH] mailbox: PCC: erroneous error message when parsing ACPI PCCT
5
6There have been multiple reports of the following error message:
7
8[ 0.068293] Error parsing PCC subspaces from PCCT
9
10This error message is not correct. In multiple cases examined, the PCCT
11(Platform Communications Channel Table) concerned is actually properly
12constructed; the problem is that acpi_pcc_probe() which reads the PCCT
13is making the assumption that the only valid PCCT is one that contains
14subtables of one of two types: ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE or
15ACPI_PCCT_TYPE_HW_REDUCED_TYPE2. The number of subtables of these
16types are counted and as long as there is at least one of the desired
17types, the acpi_pcc_probe() succeeds. When no subtables of these types
18are found, regardless of whether or not any other subtable types are
19present, the error mentioned above is reported.
20
21In the cases reported to me personally, the PCCT contains exactly one
22subtable of type ACPI_PCCT_TYPE_GENERIC_SUBSPACE. The function
23acpi_pcc_probe() does not count it as a valid subtable, so believes
24there to be no valid subtables, and hence outputs the error message.
25
26An example of the PCCT being reported as erroneous yet perfectly fine
27is the following:
28
29 Signature : "PCCT"
30 Table Length : 0000006E
31 Revision : 05
32 Checksum : A9
33 Oem ID : "XXXXXX"
34 Oem Table ID : "XXXXX "
35 Oem Revision : 00002280
36 Asl Compiler ID : "XXXX"
37 Asl Compiler Revision : 00000002
38
39 Flags (decoded below) : 00000001
40 Platform : 1
41 Reserved : 0000000000000000
42
43 Subtable Type : 00 [Generic Communications Subspace]
44 Length : 3E
45
46 Reserved : 000000000000
47 Base Address : 00000000DCE43018
48 Address Length : 0000000000001000
49
50 Doorbell Register : [Generic Address Structure]
51 Space ID : 01 [SystemIO]
52 Bit Width : 08
53 Bit Offset : 00
54 Encoded Access Width : 01 [Byte Access:8]
55 Address : 0000000000001842
56
57 Preserve Mask : 00000000000000FD
58 Write Mask : 0000000000000002
59 Command Latency : 00001388
60 Maximum Access Rate : 00000000
61 Minimum Turnaround Time : 0000
62
63To fix this, we count up all of the possible subtable types for the
64PCCT, and only report an error when there are none (which could mean
65either no subtables, or no valid subtables), or there are too many.
66We also change the logic so that if there is a valid subtable, we
67do try to initialize it per the PCCT subtable contents. This is a
68change in functionality; previously, the probe would have returned
69right after the error message and would not have tried to use any
70other subtable definition.
71
72Tested on my personal laptop which showed the error previously; the
73error message no longer appears and the laptop appears to operate
74normally.
75
76Signed-off-by: Al Stone <ahs3@redhat.com>
77Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org>
78Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
79---
80 drivers/mailbox/pcc.c | 81 ++++++++++++++++++++++++---------------------------
81 1 file changed, 38 insertions(+), 43 deletions(-)
82
83diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
84index 3ef7f036ceea..fc3c237daef2 100644
85--- a/drivers/mailbox/pcc.c
86+++ b/drivers/mailbox/pcc.c
87@@ -373,33 +373,24 @@ static const struct mbox_chan_ops pcc_chan_ops = {
88 };
89
90 /**
91- * parse_pcc_subspace - Parse the PCC table and verify PCC subspace
92- * entries. There should be one entry per PCC client.
93+ * parse_pcc_subspaces -- Count PCC subspaces defined
94 * @header: Pointer to the ACPI subtable header under the PCCT.
95 * @end: End of subtable entry.
96 *
97- * Return: 0 for Success, else errno.
98+ * Return: If we find a PCC subspace entry of a valid type, return 0.
99+ * Otherwise, return -EINVAL.
100 *
101 * This gets called for each entry in the PCC table.
102 */
103 static int parse_pcc_subspace(struct acpi_subtable_header *header,
104 const unsigned long end)
105 {
106- struct acpi_pcct_hw_reduced *pcct_ss;
107-
108- if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) {
109- pcct_ss = (struct acpi_pcct_hw_reduced *) header;
110+ struct acpi_pcct_subspace *ss = (struct acpi_pcct_subspace *) header;
111
112- if ((pcct_ss->header.type !=
113- ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE)
114- && (pcct_ss->header.type !=
115- ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2)) {
116- pr_err("Incorrect PCC Subspace type detected\n");
117- return -EINVAL;
118- }
119- }
120+ if (ss->header.type < ACPI_PCCT_TYPE_RESERVED)
121+ return 0;
122
123- return 0;
124+ return -EINVAL;
125 }
126
127 /**
128@@ -449,8 +440,8 @@ static int __init acpi_pcc_probe(void)
129 struct acpi_table_header *pcct_tbl;
130 struct acpi_subtable_header *pcct_entry;
131 struct acpi_table_pcct *acpi_pcct_tbl;
132+ struct acpi_subtable_proc proc[ACPI_PCCT_TYPE_RESERVED];
133 int count, i, rc;
134- int sum = 0;
135 acpi_status status = AE_OK;
136
137 /* Search for PCCT */
138@@ -459,43 +450,41 @@ static int __init acpi_pcc_probe(void)
139 if (ACPI_FAILURE(status) || !pcct_tbl)
140 return -ENODEV;
141
142- count = acpi_table_parse_entries(ACPI_SIG_PCCT,
143- sizeof(struct acpi_table_pcct),
144- ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE,
145- parse_pcc_subspace, MAX_PCC_SUBSPACES);
146- sum += (count > 0) ? count : 0;
147-
148- count = acpi_table_parse_entries(ACPI_SIG_PCCT,
149- sizeof(struct acpi_table_pcct),
150- ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2,
151- parse_pcc_subspace, MAX_PCC_SUBSPACES);
152- sum += (count > 0) ? count : 0;
153+ /* Set up the subtable handlers */
154+ for (i = ACPI_PCCT_TYPE_GENERIC_SUBSPACE;
155+ i < ACPI_PCCT_TYPE_RESERVED; i++) {
156+ proc[i].id = i;
157+ proc[i].count = 0;
158+ proc[i].handler = parse_pcc_subspace;
159+ }
160
161- if (sum == 0 || sum >= MAX_PCC_SUBSPACES) {
162- pr_err("Error parsing PCC subspaces from PCCT\n");
163+ count = acpi_table_parse_entries_array(ACPI_SIG_PCCT,
164+ sizeof(struct acpi_table_pcct), proc,
165+ ACPI_PCCT_TYPE_RESERVED, MAX_PCC_SUBSPACES);
166+ if (count == 0 || count > MAX_PCC_SUBSPACES) {
167+ pr_warn("Invalid PCCT: %d PCC subspaces\n", count);
168 return -EINVAL;
169 }
170
171- pcc_mbox_channels = kzalloc(sizeof(struct mbox_chan) *
172- sum, GFP_KERNEL);
173+ pcc_mbox_channels = kzalloc(sizeof(struct mbox_chan) * count, GFP_KERNEL);
174 if (!pcc_mbox_channels) {
175 pr_err("Could not allocate space for PCC mbox channels\n");
176 return -ENOMEM;
177 }
178
179- pcc_doorbell_vaddr = kcalloc(sum, sizeof(void *), GFP_KERNEL);
180+ pcc_doorbell_vaddr = kcalloc(count, sizeof(void *), GFP_KERNEL);
181 if (!pcc_doorbell_vaddr) {
182 rc = -ENOMEM;
183 goto err_free_mbox;
184 }
185
186- pcc_doorbell_ack_vaddr = kcalloc(sum, sizeof(void *), GFP_KERNEL);
187+ pcc_doorbell_ack_vaddr = kcalloc(count, sizeof(void *), GFP_KERNEL);
188 if (!pcc_doorbell_ack_vaddr) {
189 rc = -ENOMEM;
190 goto err_free_db_vaddr;
191 }
192
193- pcc_doorbell_irq = kcalloc(sum, sizeof(int), GFP_KERNEL);
194+ pcc_doorbell_irq = kcalloc(count, sizeof(int), GFP_KERNEL);
195 if (!pcc_doorbell_irq) {
196 rc = -ENOMEM;
197 goto err_free_db_ack_vaddr;
198@@ -509,18 +498,24 @@ static int __init acpi_pcc_probe(void)
199 if (acpi_pcct_tbl->flags & ACPI_PCCT_DOORBELL)
200 pcc_mbox_ctrl.txdone_irq = true;
201
202- for (i = 0; i < sum; i++) {
203+ for (i = 0; i < count; i++) {
204 struct acpi_generic_address *db_reg;
205- struct acpi_pcct_hw_reduced *pcct_ss;
206+ struct acpi_pcct_subspace *pcct_ss;
207 pcc_mbox_channels[i].con_priv = pcct_entry;
208
209- pcct_ss = (struct acpi_pcct_hw_reduced *) pcct_entry;
210+ if (pcct_entry->type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE ||
211+ pcct_entry->type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) {
212+ struct acpi_pcct_hw_reduced *pcct_hrss;
213+
214+ pcct_hrss = (struct acpi_pcct_hw_reduced *) pcct_entry;
215
216- if (pcc_mbox_ctrl.txdone_irq) {
217- rc = pcc_parse_subspace_irq(i, pcct_ss);
218- if (rc < 0)
219- goto err;
220+ if (pcc_mbox_ctrl.txdone_irq) {
221+ rc = pcc_parse_subspace_irq(i, pcct_hrss);
222+ if (rc < 0)
223+ goto err;
224+ }
225 }
226+ pcct_ss = (struct acpi_pcct_subspace *) pcct_entry;
227
228 /* If doorbell is in system memory cache the virt address */
229 db_reg = &pcct_ss->doorbell_register;
230@@ -531,7 +526,7 @@ static int __init acpi_pcc_probe(void)
231 ((unsigned long) pcct_entry + pcct_entry->length);
232 }
233
234- pcc_mbox_ctrl.num_chans = sum;
235+ pcc_mbox_ctrl.num_chans = count;
236
237 pr_info("Detected %d PCC Subspaces\n", pcc_mbox_ctrl.num_chans);
238
239
diff --git a/patches/drivers/mailbox/acpi-pcct.scc b/patches/drivers/mailbox/acpi-pcct.scc
deleted file mode 100644
index 16d8c2c..0000000
--- a/patches/drivers/mailbox/acpi-pcct.scc
+++ /dev/null
@@ -1,2 +0,0 @@
1# Upstream in kernel v4.18-rc1 and newer
2patch 0001-mailbox-PCC-erroneous-error-message-when-parsing-ACPI-PCCT.patch
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2025-11-01 20:37:41 +0000