[PATCH] acpi_pcihp: Add support for _HPX

This patch adds support for _HPX (Hot Plug Parameter Extensions)
defined in ACPI3.0a spec.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c
index afac5c3..51cb9f8 100644
--- a/drivers/pci/hotplug/acpi_pcihp.c
+++ b/drivers/pci/hotplug/acpi_pcihp.c
@@ -47,6 +47,171 @@
 
 static int debug_acpi;
 
+static acpi_status
+decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
+{
+	int i;
+	union acpi_object *fields = record->package.elements;
+	u32 revision = fields[1].integer.value;
+
+	switch (revision) {
+	case 1:
+		if (record->package.count != 6)
+			return AE_ERROR;
+		for (i = 2; i < 6; i++)
+			if (fields[i].type != ACPI_TYPE_INTEGER)
+				return AE_ERROR;
+		hpx->t0 = &hpx->type0_data;
+		hpx->t0->revision        = revision;
+		hpx->t0->cache_line_size = fields[2].integer.value;
+		hpx->t0->latency_timer   = fields[3].integer.value;
+		hpx->t0->enable_serr     = fields[4].integer.value;
+		hpx->t0->enable_perr     = fields[5].integer.value;
+		break;
+	default:
+		printk(KERN_WARNING
+		       "%s: Type 0 Revision %d record not supported\n",
+		       __FUNCTION__, revision);
+		return AE_ERROR;
+	}
+	return AE_OK;
+}
+
+static acpi_status
+decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
+{
+	int i;
+	union acpi_object *fields = record->package.elements;
+	u32 revision = fields[1].integer.value;
+
+	switch (revision) {
+	case 1:
+		if (record->package.count != 5)
+			return AE_ERROR;
+		for (i = 2; i < 5; i++)
+			if (fields[i].type != ACPI_TYPE_INTEGER)
+				return AE_ERROR;
+		hpx->t1 = &hpx->type1_data;
+		hpx->t1->revision      = revision;
+		hpx->t1->max_mem_read  = fields[2].integer.value;
+		hpx->t1->avg_max_split = fields[3].integer.value;
+		hpx->t1->tot_max_split = fields[4].integer.value;
+		break;
+	default:
+		printk(KERN_WARNING
+		       "%s: Type 1 Revision %d record not supported\n",
+		       __FUNCTION__, revision);
+		return AE_ERROR;
+	}
+	return AE_OK;
+}
+
+static acpi_status
+decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
+{
+	int i;
+	union acpi_object *fields = record->package.elements;
+	u32 revision = fields[1].integer.value;
+
+	switch (revision) {
+	case 1:
+		if (record->package.count != 18)
+			return AE_ERROR;
+		for (i = 2; i < 18; i++)
+			if (fields[i].type != ACPI_TYPE_INTEGER)
+				return AE_ERROR;
+		hpx->t2 = &hpx->type2_data;
+		hpx->t2->revision      = revision;
+		hpx->t2->unc_err_mask_and      = fields[2].integer.value;
+		hpx->t2->unc_err_mask_or       = fields[3].integer.value;
+		hpx->t2->unc_err_sever_and     = fields[4].integer.value;
+		hpx->t2->unc_err_sever_or      = fields[5].integer.value;
+		hpx->t2->cor_err_mask_and      = fields[6].integer.value;
+		hpx->t2->cor_err_mask_or       = fields[7].integer.value;
+		hpx->t2->adv_err_cap_and       = fields[8].integer.value;
+		hpx->t2->adv_err_cap_or        = fields[9].integer.value;
+		hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
+		hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
+		hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
+		hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
+		hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
+		hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
+		hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
+		hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
+		break;
+	default:
+		printk(KERN_WARNING
+		       "%s: Type 2 Revision %d record not supported\n",
+		       __FUNCTION__, revision);
+		return AE_ERROR;
+	}
+	return AE_OK;
+}
+
+static acpi_status
+acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
+{
+	acpi_status status;
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	union acpi_object *package, *record, *fields;
+	u32 type;
+	int i;
+
+	/* Clear the return buffer with zeros */
+	memset(hpx, 0, sizeof(struct hotplug_params));
+
+	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	package = (union acpi_object *)buffer.pointer;
+	if (package->type != ACPI_TYPE_PACKAGE) {
+		status = AE_ERROR;
+		goto exit;
+	}
+
+	for (i = 0; i < package->package.count; i++) {
+		record = &package->package.elements[i];
+		if (record->type != ACPI_TYPE_PACKAGE) {
+			status = AE_ERROR;
+			goto exit;
+		}
+
+		fields = record->package.elements;
+		if (fields[0].type != ACPI_TYPE_INTEGER ||
+		    fields[1].type != ACPI_TYPE_INTEGER) {
+			status = AE_ERROR;
+			goto exit;
+		}
+
+		type = fields[0].integer.value;
+		switch (type) {
+		case 0:
+			status = decode_type0_hpx_record(record, hpx);
+			if (ACPI_FAILURE(status))
+				goto exit;
+			break;
+		case 1:
+			status = decode_type1_hpx_record(record, hpx);
+			if (ACPI_FAILURE(status))
+				goto exit;
+			break;
+		case 2:
+			status = decode_type2_hpx_record(record, hpx);
+			if (ACPI_FAILURE(status))
+				goto exit;
+			break;
+		default:
+			printk(KERN_ERR "%s: Type %d record not supported\n",
+			       __FUNCTION__, type);
+			status = AE_ERROR;
+			goto exit;
+		}
+	}
+ exit:
+	kfree(buffer.pointer);
+	return status;
+}
 
 static acpi_status
 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
@@ -60,6 +225,9 @@
 
 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 
+	/* Clear the return buffer with zeros */
+	memset(hpp, 0, sizeof(struct hotplug_params));
+
 	/* get _hpp */
 	status = acpi_evaluate_object(handle, METHOD_NAME__HPP, NULL, &ret_buf);
 	switch (status) {
@@ -108,15 +276,16 @@
 		}
 	}
 
-	hpp->cache_line_size = nui[0];
-	hpp->latency_timer = nui[1];
-	hpp->enable_serr = nui[2];
-	hpp->enable_perr = nui[3];
+	hpp->t0 = &hpp->type0_data;
+	hpp->t0->cache_line_size = nui[0];
+	hpp->t0->latency_timer = nui[1];
+	hpp->t0->enable_serr = nui[2];
+	hpp->t0->enable_perr = nui[3];
 
-	pr_debug("  _HPP: cache_line_size=0x%x\n", hpp->cache_line_size);
-	pr_debug("  _HPP: latency timer  =0x%x\n", hpp->latency_timer);
-	pr_debug("  _HPP: enable SERR    =0x%x\n", hpp->enable_serr);
-	pr_debug("  _HPP: enable PERR    =0x%x\n", hpp->enable_perr);
+	pr_debug("  _HPP: cache_line_size=0x%x\n", hpp->t0->cache_line_size);
+	pr_debug("  _HPP: latency timer  =0x%x\n", hpp->t0->latency_timer);
+	pr_debug("  _HPP: enable SERR    =0x%x\n", hpp->t0->enable_serr);
+	pr_debug("  _HPP: enable PERR    =0x%x\n", hpp->t0->enable_perr);
 
 free_and_return:
 	kfree(string.pointer);
@@ -188,6 +357,9 @@
 	 * this pci dev. If we don't find any _HPP, use hardcoded defaults
 	 */
 	while (handle) {
+		status = acpi_run_hpx(handle, hpp);
+		if (ACPI_SUCCESS(status))
+			break;
 		status = acpi_run_hpp(handle, hpp);
 		if (ACPI_SUCCESS(status))
 			break;