[deliverable/linux.git] / arch / powerpc / platforms / pseries / msi.c

/*
 * Copyright 2006 Jake Moilanen <moilanen@austin.ibm.com>, IBM Corp.
 * Copyright 2006-2007 Michael Ellerman, IBM Corp.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; version 2 of the
 * License.
 *
 */

#include <linux/device.h>
#include <linux/irq.h>
#include <linux/msi.h>

#include <asm/rtas.h>
#include <asm/hw_irq.h>
#include <asm/ppc-pci.h>

static int query_token, change_token;

#define RTAS_QUERY_FN		0
#define RTAS_CHANGE_FN		1
#define RTAS_RESET_FN		2
#define RTAS_CHANGE_MSI_FN	3
#define RTAS_CHANGE_MSIX_FN	4

static struct pci_dn *get_pdn(struct pci_dev *pdev)
{
	struct device_node *dn;
	struct pci_dn *pdn;

	dn = pci_device_to_OF_node(pdev);
	if (!dn) {
		dev_dbg(&pdev->dev, "rtas_msi: No OF device node\n");
		return NULL;
	}

	pdn = PCI_DN(dn);
	if (!pdn) {
		dev_dbg(&pdev->dev, "rtas_msi: No PCI DN\n");
		return NULL;
	}

	return pdn;
}

/* RTAS Helpers */

static int rtas_change_msi(struct pci_dn *pdn, u32 func, u32 num_irqs)
{
	u32 addr, seq_num, rtas_ret[3];
	unsigned long buid;
	int rc;

	addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
	buid = pdn->phb->buid;

	seq_num = 1;
	do {
		if (func == RTAS_CHANGE_MSI_FN || func == RTAS_CHANGE_MSIX_FN)
			rc = rtas_call(change_token, 6, 4, rtas_ret, addr,
					BUID_HI(buid), BUID_LO(buid),
					func, num_irqs, seq_num);
		else
			rc = rtas_call(change_token, 6, 3, rtas_ret, addr,
					BUID_HI(buid), BUID_LO(buid),
					func, num_irqs, seq_num);

		seq_num = rtas_ret[1];
	} while (rtas_busy_delay(rc));

	/*
	 * If the RTAS call succeeded, return the number of irqs allocated.
	 * If not, make sure we return a negative error code.
	 */
	if (rc == 0)
		rc = rtas_ret[0];
	else if (rc > 0)
		rc = -rc;

	pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d), got %d rc = %d\n",
		 func, num_irqs, rtas_ret[0], rc);

	return rc;
}

static void rtas_disable_msi(struct pci_dev *pdev)
{
	struct pci_dn *pdn;

	pdn = get_pdn(pdev);
	if (!pdn)
		return;

	if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0)
		pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
}

static int rtas_query_irq_number(struct pci_dn *pdn, int offset)
{
	u32 addr, rtas_ret[2];
	unsigned long buid;
	int rc;

	addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
	buid = pdn->phb->buid;

	do {
		rc = rtas_call(query_token, 4, 3, rtas_ret, addr,
			       BUID_HI(buid), BUID_LO(buid), offset);
	} while (rtas_busy_delay(rc));

	if (rc) {
		pr_debug("rtas_msi: error (%d) querying source number\n", rc);
		return rc;
	}

	return rtas_ret[0];
}

static void rtas_teardown_msi_irqs(struct pci_dev *pdev)
{
	struct msi_desc *entry;

	list_for_each_entry(entry, &pdev->msi_list, list) {
		if (entry->irq == NO_IRQ)
			continue;

		set_irq_msi(entry->irq, NULL);
		irq_dispose_mapping(entry->irq);
	}

	rtas_disable_msi(pdev);
}

static int check_req(struct pci_dev *pdev, int nvec, char *prop_name)
{
	struct device_node *dn;
	struct pci_dn *pdn;
	const u32 *req_msi;

	pdn = get_pdn(pdev);
	if (!pdn)
		return -ENODEV;

	dn = pdn->node;

	req_msi = of_get_property(dn, prop_name, NULL);
	if (!req_msi) {
		pr_debug("rtas_msi: No %s on %s\n", prop_name, dn->full_name);
		return -ENOENT;
	}

	if (*req_msi < nvec) {
		pr_debug("rtas_msi: %s requests < %d MSIs\n", prop_name, nvec);

		if (*req_msi == 0) /* Be paranoid */
			return -ENOSPC;

		return *req_msi;
	}

	return 0;
}

static int check_req_msi(struct pci_dev *pdev, int nvec)
{
	return check_req(pdev, nvec, "ibm,req#msi");
}

static int check_req_msix(struct pci_dev *pdev, int nvec)
{
	return check_req(pdev, nvec, "ibm,req#msi-x");
}

/* Quota calculation */

static struct device_node *find_pe_total_msi(struct pci_dev *dev, int *total)
{
	struct device_node *dn;
	const u32 *p;

	dn = of_node_get(pci_device_to_OF_node(dev));
	while (dn) {
		p = of_get_property(dn, "ibm,pe-total-#msi", NULL);
		if (p) {
			pr_debug("rtas_msi: found prop on dn %s\n",
				dn->full_name);
			*total = *p;
			return dn;
		}

		dn = of_get_next_parent(dn);
	}

	return NULL;
}

static struct device_node *find_pe_dn(struct pci_dev *dev, int *total)
{
	struct device_node *dn;

	/* Found our PE and assume 8 at that point. */

	dn = pci_device_to_OF_node(dev);
	if (!dn)
		return NULL;

	dn = find_device_pe(dn);
	if (!dn)
		return NULL;

	/* We actually want the parent */
	dn = of_get_parent(dn);
	if (!dn)
		return NULL;

	/* Hardcode of 8 for old firmwares */
	*total = 8;
	pr_debug("rtas_msi: using PE dn %s\n", dn->full_name);

	return dn;
}

struct msi_counts {
	struct device_node *requestor;
	int num_devices;
	int request;
	int quota;
	int spare;
	int over_quota;
};

static void *count_non_bridge_devices(struct device_node *dn, void *data)
{
	struct msi_counts *counts = data;
	const u32 *p;
	u32 class;

	pr_debug("rtas_msi: counting %s\n", dn->full_name);

	p = of_get_property(dn, "class-code", NULL);
	class = p ? *p : 0;

	if ((class >> 8) != PCI_CLASS_BRIDGE_PCI)
		counts->num_devices++;

	return NULL;
}

static void *count_spare_msis(struct device_node *dn, void *data)
{
	struct msi_counts *counts = data;
	const u32 *p;
	int req;

	if (dn == counts->requestor)
		req = counts->request;
	else {
		/* We don't know if a driver will try to use MSI or MSI-X,
		 * so we just have to punt and use the larger of the two. */
		req = 0;
		p = of_get_property(dn, "ibm,req#msi", NULL);
		if (p)
			req = *p;

		p = of_get_property(dn, "ibm,req#msi-x", NULL);
		if (p)
			req = max(req, (int)*p);
	}

	if (req < counts->quota)
		counts->spare += counts->quota - req;
	else if (req > counts->quota)
		counts->over_quota++;

	return NULL;
}

static int msi_quota_for_device(struct pci_dev *dev, int request)
{
	struct device_node *pe_dn;
	struct msi_counts counts;
	int total;

	pr_debug("rtas_msi: calc quota for %s, request %d\n", pci_name(dev),
		  request);

	pe_dn = find_pe_total_msi(dev, &total);
	if (!pe_dn)
		pe_dn = find_pe_dn(dev, &total);

	if (!pe_dn) {
		pr_err("rtas_msi: couldn't find PE for %s\n", pci_name(dev));
		goto out;
	}

	pr_debug("rtas_msi: found PE %s\n", pe_dn->full_name);

	memset(&counts, 0, sizeof(struct msi_counts));

	/* Work out how many devices we have below this PE */
	traverse_pci_devices(pe_dn, count_non_bridge_devices, &counts);

	if (counts.num_devices == 0) {
		pr_err("rtas_msi: found 0 devices under PE for %s\n",
			pci_name(dev));
		goto out;
	}

	counts.quota = total / counts.num_devices;
	if (request <= counts.quota)
		goto out;

	/* else, we have some more calculating to do */
	counts.requestor = pci_device_to_OF_node(dev);
	counts.request = request;
	traverse_pci_devices(pe_dn, count_spare_msis, &counts);

	/* If the quota isn't an integer multiple of the total, we can
	 * use the remainder as spare MSIs for anyone that wants them. */
	counts.spare += total % counts.num_devices;

	/* Divide any spare by the number of over-quota requestors */
	if (counts.over_quota)
		counts.quota += counts.spare / counts.over_quota;

	/* And finally clamp the request to the possibly adjusted quota */
	request = min(counts.quota, request);

	pr_debug("rtas_msi: request clamped to quota %d\n", request);
out:
	of_node_put(pe_dn);

	return request;
}

static int rtas_msi_check_device(struct pci_dev *pdev, int nvec, int type)
{
	int quota, rc;

	if (type == PCI_CAP_ID_MSIX)
		rc = check_req_msix(pdev, nvec);
	else
		rc = check_req_msi(pdev, nvec);

	if (rc)
		return rc;

	quota = msi_quota_for_device(pdev, nvec);

	if (quota && quota < nvec)
		return quota;

	return 0;
}

static int rtas_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
{
	struct pci_dn *pdn;
	int hwirq, virq, i, rc;
	struct msi_desc *entry;
	struct msi_msg msg;

	pdn = get_pdn(pdev);
	if (!pdn)
		return -ENODEV;

	/*
	 * Try the new more explicit firmware interface, if that fails fall
	 * back to the old interface. The old interface is known to never
	 * return MSI-Xs.
	 */
	if (type == PCI_CAP_ID_MSI) {
		rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);

		if (rc < 0) {
			pr_debug("rtas_msi: trying the old firmware call.\n");
			rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
		}
	} else
		rc = rtas_change_msi(pdn, RTAS_CHANGE_MSIX_FN, nvec);

	if (rc != nvec) {
		pr_debug("rtas_msi: rtas_change_msi() failed\n");
		return rc;
	}

	i = 0;
	list_for_each_entry(entry, &pdev->msi_list, list) {
		hwirq = rtas_query_irq_number(pdn, i++);
		if (hwirq < 0) {
			pr_debug("rtas_msi: error (%d) getting hwirq\n", rc);
			return hwirq;
		}

		virq = irq_create_mapping(NULL, hwirq);

		if (virq == NO_IRQ) {
			pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
			return -ENOSPC;
		}

		dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
		set_irq_msi(virq, entry);

		/* Read config space back so we can restore after reset */
		read_msi_msg(virq, &msg);
		entry->msg = msg;

		unmask_msi_irq(virq);
	}

	return 0;
}

static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
{
	/* No LSI -> leave MSIs (if any) configured */
	if (pdev->irq == NO_IRQ) {
		dev_dbg(&pdev->dev, "rtas_msi: no LSI, nothing to do.\n");
		return;
	}

	/* No MSI -> MSIs can't have been assigned by fw, leave LSI */
	if (check_req_msi(pdev, 1) && check_req_msix(pdev, 1)) {
		dev_dbg(&pdev->dev, "rtas_msi: no req#msi/x, nothing to do.\n");
		return;
	}

	dev_dbg(&pdev->dev, "rtas_msi: disabling existing MSI.\n");
	rtas_disable_msi(pdev);
}

static int rtas_msi_init(void)
{
	query_token  = rtas_token("ibm,query-interrupt-source-number");
	change_token = rtas_token("ibm,change-msi");

	if ((query_token == RTAS_UNKNOWN_SERVICE) ||
			(change_token == RTAS_UNKNOWN_SERVICE)) {
		pr_debug("rtas_msi: no RTAS tokens, no MSI support.\n");
		return -1;
	}

	pr_debug("rtas_msi: Registering RTAS MSI callbacks.\n");

	WARN_ON(ppc_md.setup_msi_irqs);
	ppc_md.setup_msi_irqs = rtas_setup_msi_irqs;
	ppc_md.teardown_msi_irqs = rtas_teardown_msi_irqs;
	ppc_md.msi_check_device = rtas_msi_check_device;

	WARN_ON(ppc_md.pci_irq_fixup);
	ppc_md.pci_irq_fixup = rtas_msi_pci_irq_fixup;

	return 0;
}
arch_initcall(rtas_msi_init);
Commit	Line	Data
85f2bf9f ME	1	/*
	2	* Copyright 2006 Jake Moilanen <moilanen@austin.ibm.com>, IBM Corp.
	3	* Copyright 2006-2007 Michael Ellerman, IBM Corp.
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License
	7	* as published by the Free Software Foundation; version 2 of the
	8	* License.
	9	*
	10	*/
	11
	12	#include <linux/device.h>
	13	#include <linux/irq.h>
	14	#include <linux/msi.h>
	15
	16	#include <asm/rtas.h>
	17	#include <asm/hw_irq.h>
	18	#include <asm/ppc-pci.h>
	19
	20	static int query_token, change_token;
	21
	22	#define RTAS_QUERY_FN 0
	23	#define RTAS_CHANGE_FN 1
	24	#define RTAS_RESET_FN 2
	25	#define RTAS_CHANGE_MSI_FN 3
	26	#define RTAS_CHANGE_MSIX_FN 4
	27
	28	static struct pci_dn get_pdn(struct pci_dev pdev)
	29	{
	30	struct device_node *dn;
	31	struct pci_dn *pdn;
	32
	33	dn = pci_device_to_OF_node(pdev);
	34	if (!dn) {
	35	dev_dbg(&pdev->dev, "rtas_msi: No OF device node\n");
	36	return NULL;
	37	}
	38
	39	pdn = PCI_DN(dn);
	40	if (!pdn) {
	41	dev_dbg(&pdev->dev, "rtas_msi: No PCI DN\n");
	42	return NULL;
	43	}
	44
	45	return pdn;
	46	}
	47
	48	/* RTAS Helpers */
	49
	50	static int rtas_change_msi(struct pci_dn *pdn, u32 func, u32 num_irqs)
	51	{
	52	u32 addr, seq_num, rtas_ret[3];
	53	unsigned long buid;
	54	int rc;
	55
	56	addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
	57	buid = pdn->phb->buid;
	58
	59	seq_num = 1;
	60	do {
	61	if (func == RTAS_CHANGE_MSI_FN \|\| func == RTAS_CHANGE_MSIX_FN)
	62	rc = rtas_call(change_token, 6, 4, rtas_ret, addr,
	63	BUID_HI(buid), BUID_LO(buid),
	64	func, num_irqs, seq_num);
65	else
66	rc = rtas_call(change_token, 6, 3, rtas_ret, addr,
67	BUID_HI(buid), BUID_LO(buid),
68	func, num_irqs, seq_num);
69
70	seq_num = rtas_ret[1];
71	} while (rtas_busy_delay(rc));
72
d385366a	73	/*
6071ed04 ME	74	* If the RTAS call succeeded, return the number of irqs allocated.
6071ed04 ME	75	* If not, make sure we return a negative error code.
d385366a	76	*/
6071ed04 ME	77	if (rc == 0)
	78	rc = rtas_ret[0];
	79	else if (rc > 0)
	80	rc = -rc;
85f2bf9f	81
d385366a ME	82	pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d), got %d rc = %d\n",
d385366a ME	83	func, num_irqs, rtas_ret[0], rc);
85f2bf9f ME	84
	85	return rc;
	86	}
	87
	88	static void rtas_disable_msi(struct pci_dev *pdev)
	89	{
	90	struct pci_dn *pdn;
	91
	92	pdn = get_pdn(pdev);
	93	if (!pdn)
	94	return;
	95
6071ed04	96	if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0)
85f2bf9f ME	97	pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
	98	}
	99
	100	static int rtas_query_irq_number(struct pci_dn *pdn, int offset)
	101	{
	102	u32 addr, rtas_ret[2];
	103	unsigned long buid;
	104	int rc;
	105
	106	addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
	107	buid = pdn->phb->buid;
	108
	109	do {
	110	rc = rtas_call(query_token, 4, 3, rtas_ret, addr,
	111	BUID_HI(buid), BUID_LO(buid), offset);
	112	} while (rtas_busy_delay(rc));
	113
	114	if (rc) {
	115	pr_debug("rtas_msi: error (%d) querying source number\n", rc);
	116	return rc;
	117	}
	118
	119	return rtas_ret[0];
	120	}
	121
	122	static void rtas_teardown_msi_irqs(struct pci_dev *pdev)
	123	{
	124	struct msi_desc *entry;
	125
	126	list_for_each_entry(entry, &pdev->msi_list, list) {
	127	if (entry->irq == NO_IRQ)
	128	continue;
	129
	130	set_irq_msi(entry->irq, NULL);
	131	irq_dispose_mapping(entry->irq);
	132	}
	133
	134	rtas_disable_msi(pdev);
	135	}
	136
3a51c0cb	137	static int check_req(struct pci_dev pdev, int nvec, char prop_name)
85f2bf9f ME	138	{
	139	struct device_node *dn;
	140	struct pci_dn *pdn;
	141	const u32 *req_msi;
	142
	143	pdn = get_pdn(pdev);
	144	if (!pdn)
	145	return -ENODEV;
	146
	147	dn = pdn->node;
	148
3a51c0cb	149	req_msi = of_get_property(dn, prop_name, NULL);
85f2bf9f	150	if (!req_msi) {
3a51c0cb	151	pr_debug("rtas_msi: No %s on %s\n", prop_name, dn->full_name);
85f2bf9f ME	152	return -ENOENT;
	153	}
	154
	155	if (*req_msi < nvec) {
3a51c0cb	156	pr_debug("rtas_msi: %s requests < %d MSIs\n", prop_name, nvec);
d523cc37 ME	157
	158	if (req_msi == 0) / Be paranoid */
	159	return -ENOSPC;
	160
	161	return *req_msi;
85f2bf9f ME	162	}
	163
	164	return 0;
	165	}
	166
3a51c0cb ME	167	static int check_req_msi(struct pci_dev *pdev, int nvec)
	168	{
	169	return check_req(pdev, nvec, "ibm,req#msi");
	170	}
	171
	172	static int check_req_msix(struct pci_dev *pdev, int nvec)
	173	{
	174	return check_req(pdev, nvec, "ibm,req#msi-x");
	175	}
	176
448e2ca0 ME	177	/* Quota calculation */
	178
	179	static struct device_node find_pe_total_msi(struct pci_dev dev, int *total)
	180	{
	181	struct device_node *dn;
	182	const u32 *p;
	183
	184	dn = of_node_get(pci_device_to_OF_node(dev));
	185	while (dn) {
	186	p = of_get_property(dn, "ibm,pe-total-#msi", NULL);
	187	if (p) {
	188	pr_debug("rtas_msi: found prop on dn %s\n",
	189	dn->full_name);
	190	total = p;
	191	return dn;
	192	}
	193
	194	dn = of_get_next_parent(dn);
	195	}
	196
	197	return NULL;
	198	}
	199
	200	static struct device_node find_pe_dn(struct pci_dev dev, int *total)
	201	{
	202	struct device_node *dn;
	203
	204	/* Found our PE and assume 8 at that point. */
	205
	206	dn = pci_device_to_OF_node(dev);
	207	if (!dn)
	208	return NULL;
	209
	210	dn = find_device_pe(dn);
	211	if (!dn)
	212	return NULL;
	213
	214	/* We actually want the parent */
	215	dn = of_get_parent(dn);
	216	if (!dn)
	217	return NULL;
	218
	219	/* Hardcode of 8 for old firmwares */
	220	*total = 8;
	221	pr_debug("rtas_msi: using PE dn %s\n", dn->full_name);
	222
	223	return dn;
	224	}
	225
	226	struct msi_counts {
	227	struct device_node *requestor;
	228	int num_devices;
	229	int request;
	230	int quota;
	231	int spare;
	232	int over_quota;
	233	};
	234
	235	static void count_non_bridge_devices(struct device_node dn, void *data)
	236	{
	237	struct msi_counts *counts = data;
	238	const u32 *p;
	239	u32 class;
	240
241	pr_debug("rtas_msi: counting %s\n", dn->full_name);
242
243	p = of_get_property(dn, "class-code", NULL);
244	class = p ? *p : 0;
245
246	if ((class >> 8) != PCI_CLASS_BRIDGE_PCI)
247	counts->num_devices++;
248
249	return NULL;
250	}
251
252	static void count_spare_msis(struct device_node dn, void *data)
253	{
254	struct msi_counts *counts = data;
255	const u32 *p;
256	int req;
257
258	if (dn == counts->requestor)
259	req = counts->request;
260	else {
261	/* We don't know if a driver will try to use MSI or MSI-X,
262	* so we just have to punt and use the larger of the two. */
263	req = 0;
264	p = of_get_property(dn, "ibm,req#msi", NULL);
265	if (p)
266	req = *p;
267
268	p = of_get_property(dn, "ibm,req#msi-x", NULL);
269	if (p)
270	req = max(req, (int)*p);
271	}
272
273	if (req < counts->quota)
274	counts->spare += counts->quota - req;
275	else if (req > counts->quota)
276	counts->over_quota++;
277
278	return NULL;
279	}
280
281	static int msi_quota_for_device(struct pci_dev *dev, int request)
282	{
283	struct device_node *pe_dn;
284	struct msi_counts counts;
285	int total;
286
287	pr_debug("rtas_msi: calc quota for %s, request %d\n", pci_name(dev),
288	request);
289
290	pe_dn = find_pe_total_msi(dev, &total);
291	if (!pe_dn)
292	pe_dn = find_pe_dn(dev, &total);
293
294	if (!pe_dn) {
295	pr_err("rtas_msi: couldn't find PE for %s\n", pci_name(dev));
296	goto out;
297	}
298
299	pr_debug("rtas_msi: found PE %s\n", pe_dn->full_name);
300
301	memset(&counts, 0, sizeof(struct msi_counts));
302
303	/* Work out how many devices we have below this PE */
304	traverse_pci_devices(pe_dn, count_non_bridge_devices, &counts);
305
306	if (counts.num_devices == 0) {
307	pr_err("rtas_msi: found 0 devices under PE for %s\n",
308	pci_name(dev));
309	goto out;
310	}
311
312	counts.quota = total / counts.num_devices;
313	if (request <= counts.quota)
314	goto out;
315
316	/* else, we have some more calculating to do */
317	counts.requestor = pci_device_to_OF_node(dev);
318	counts.request = request;
319	traverse_pci_devices(pe_dn, count_spare_msis, &counts);
320
321	/* If the quota isn't an integer multiple of the total, we can
322	* use the remainder as spare MSIs for anyone that wants them. */
323	counts.spare += total % counts.num_devices;
324
325	/* Divide any spare by the number of over-quota requestors */
326	if (counts.over_quota)
327	counts.quota += counts.spare / counts.over_quota;
328
329	/* And finally clamp the request to the possibly adjusted quota */
330	request = min(counts.quota, request);
331
332	pr_debug("rtas_msi: request clamped to quota %d\n", request);
333	out:
334	of_node_put(pe_dn);
335
336	return request;
337	}
338
85f2bf9f ME	339	static int rtas_msi_check_device(struct pci_dev *pdev, int nvec, int type)
85f2bf9f ME	340	{
448e2ca0 ME	341	int quota, rc;
448e2ca0 ME	342
85f2bf9f	343	if (type == PCI_CAP_ID_MSIX)
448e2ca0 ME	344	rc = check_req_msix(pdev, nvec);
	345	else
	346	rc = check_req_msi(pdev, nvec);
	347
	348	if (rc)
	349	return rc;
85f2bf9f	350
448e2ca0 ME	351	quota = msi_quota_for_device(pdev, nvec);
	352
	353	if (quota && quota < nvec)
	354	return quota;
	355
	356	return 0;
85f2bf9f ME	357	}
	358
	359	static int rtas_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
	360	{
	361	struct pci_dn *pdn;
	362	int hwirq, virq, i, rc;
	363	struct msi_desc *entry;
1db3e890	364	struct msi_msg msg;
85f2bf9f ME	365
	366	pdn = get_pdn(pdev);
	367	if (!pdn)
	368	return -ENODEV;
	369
	370	/*
	371	* Try the new more explicit firmware interface, if that fails fall
	372	* back to the old interface. The old interface is known to never
	373	* return MSI-Xs.
	374	*/
	375	if (type == PCI_CAP_ID_MSI) {
	376	rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
	377
6071ed04	378	if (rc < 0) {
85f2bf9f ME	379	pr_debug("rtas_msi: trying the old firmware call.\n");
	380	rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
	381	}
	382	} else
	383	rc = rtas_change_msi(pdn, RTAS_CHANGE_MSIX_FN, nvec);
	384
6071ed04	385	if (rc != nvec) {
85f2bf9f	386	pr_debug("rtas_msi: rtas_change_msi() failed\n");
fcbe8090	387	return rc;
85f2bf9f ME	388	}
	389
	390	i = 0;
	391	list_for_each_entry(entry, &pdev->msi_list, list) {
e27ed698	392	hwirq = rtas_query_irq_number(pdn, i++);
85f2bf9f	393	if (hwirq < 0) {
85f2bf9f	394	pr_debug("rtas_msi: error (%d) getting hwirq\n", rc);
fcbe8090	395	return hwirq;
85f2bf9f ME	396	}
	397
	398	virq = irq_create_mapping(NULL, hwirq);
	399
	400	if (virq == NO_IRQ) {
	401	pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
fcbe8090	402	return -ENOSPC;
85f2bf9f ME	403	}
	404
	405	dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
	406	set_irq_msi(virq, entry);
1db3e890 ME	407
	408	/* Read config space back so we can restore after reset */
	409	read_msi_msg(virq, &msg);
	410	entry->msg = msg;
	411
85f2bf9f ME	412	unmask_msi_irq(virq);
	413	}
	414
	415	return 0;
85f2bf9f ME	416	}
	417
	418	static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
	419	{
	420	/* No LSI -> leave MSIs (if any) configured */
	421	if (pdev->irq == NO_IRQ) {
	422	dev_dbg(&pdev->dev, "rtas_msi: no LSI, nothing to do.\n");
	423	return;
	424	}
	425
	426	/* No MSI -> MSIs can't have been assigned by fw, leave LSI */
649781f8 ME	427	if (check_req_msi(pdev, 1) && check_req_msix(pdev, 1)) {
649781f8 ME	428	dev_dbg(&pdev->dev, "rtas_msi: no req#msi/x, nothing to do.\n");
85f2bf9f ME	429	return;
	430	}
	431
	432	dev_dbg(&pdev->dev, "rtas_msi: disabling existing MSI.\n");
	433	rtas_disable_msi(pdev);
	434	}
	435
	436	static int rtas_msi_init(void)
	437	{
	438	query_token = rtas_token("ibm,query-interrupt-source-number");
	439	change_token = rtas_token("ibm,change-msi");
	440
	441	if ((query_token == RTAS_UNKNOWN_SERVICE) \|\|
	442	(change_token == RTAS_UNKNOWN_SERVICE)) {
	443	pr_debug("rtas_msi: no RTAS tokens, no MSI support.\n");
	444	return -1;
	445	}
	446
	447	pr_debug("rtas_msi: Registering RTAS MSI callbacks.\n");
	448
	449	WARN_ON(ppc_md.setup_msi_irqs);
	450	ppc_md.setup_msi_irqs = rtas_setup_msi_irqs;
	451	ppc_md.teardown_msi_irqs = rtas_teardown_msi_irqs;
	452	ppc_md.msi_check_device = rtas_msi_check_device;
	453
	454	WARN_ON(ppc_md.pci_irq_fixup);
	455	ppc_md.pci_irq_fixup = rtas_msi_pci_irq_fixup;
	456
	457	return 0;
	458	}
	459	arch_initcall(rtas_msi_init);