cxl: Add guest-specific code

The new of.c file contains code to parse the device tree to find out
about cxl adapters and AFUs.

guest.c implements the guest-specific callbacks for the backend API.

The process element ID is not known until the context is attached, so
we have to separate the context ID assigned by the cxl driver from the
process element ID visible to the user applications. In bare-metal,
the 2 IDs match.

Co-authored-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
[mpe: Fix SMP=n build, fix PSERIES=n build, minor whitespace fixes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 513 insertions, 0 deletions

diff --git a/drivers/misc/cxl/of.c b/drivers/misc/cxl/of.c
new file mode 100644
index 000000000000..edc458395f68
--- /dev/null
+++ b/drivers/misc/cxl/of.c
@@ -0,0 +1,513 @@
+/*
+ * Copyright 2015 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+
+#include "cxl.h"
+
+
+static const __be32 *read_prop_string(const struct device_node *np,
+				const char *prop_name)
+{
+	const __be32 *prop;
+
+	prop = of_get_property(np, prop_name, NULL);
+	if (cxl_verbose && prop)
+		pr_info("%s: %s\n", prop_name, (char *) prop);
+	return prop;
+}
+
+static const __be32 *read_prop_dword(const struct device_node *np,
+				const char *prop_name, u32 *val)
+{
+	const __be32 *prop;
+
+	prop = of_get_property(np, prop_name, NULL);
+	if (prop)
+		*val = be32_to_cpu(prop[0]);
+	if (cxl_verbose && prop)
+		pr_info("%s: %#x (%u)\n", prop_name, *val, *val);
+	return prop;
+}
+
+static const __be64 *read_prop64_dword(const struct device_node *np,
+				const char *prop_name, u64 *val)
+{
+	const __be64 *prop;
+
+	prop = of_get_property(np, prop_name, NULL);
+	if (prop)
+		*val = be64_to_cpu(prop[0]);
+	if (cxl_verbose && prop)
+		pr_info("%s: %#llx (%llu)\n", prop_name, *val, *val);
+	return prop;
+}
+
+
+static int read_handle(struct device_node *np, u64 *handle)
+{
+	const __be32 *prop;
+	u64 size;
+
+	/* Get address and size of the node */
+	prop = of_get_address(np, 0, &size, NULL);
+	if (size)
+		return -EINVAL;
+
+	/* Helper to read a big number; size is in cells (not bytes) */
+	*handle = of_read_number(prop, of_n_addr_cells(np));
+	return 0;
+}
+
+static int read_phys_addr(struct device_node *np, char *prop_name,
+			struct cxl_afu *afu)
+{
+	int i, len, entry_size, naddr, nsize, type;
+	u64 addr, size;
+	const __be32 *prop;
+
+	naddr = of_n_addr_cells(np);
+	nsize = of_n_size_cells(np);
+
+	prop = of_get_property(np, prop_name, &len);
+	if (prop) {
+		entry_size = naddr + nsize;
+		for (i = 0; i < (len / 4); i += entry_size, prop += entry_size) {
+			type = be32_to_cpu(prop[0]);
+			addr = of_read_number(prop, naddr);
+			size = of_read_number(&prop[naddr], nsize);
+			switch (type) {
+			case 0: /* unit address */
+				afu->guest->handle = addr;
+				break;
+			case 1: /* p2 area */
+				afu->guest->p2n_phys += addr;
+				afu->guest->p2n_size = size;
+				break;
+			case 2: /* problem state area */
+				afu->psn_phys += addr;
+				afu->adapter->ps_size = size;
+				break;
+			default:
+				pr_err("Invalid address type %d found in %s property of AFU\n",
+					type, prop_name);
+				return -EINVAL;
+			}
+			if (cxl_verbose)
+				pr_info("%s: %#x %#llx (size %#llx)\n",
+					prop_name, type, addr, size);
+		}
+	}
+	return 0;
+}
+
+static int read_vpd(struct cxl *adapter, struct cxl_afu *afu)
+{
+	char vpd[256];
+	int rc;
+	size_t len = sizeof(vpd);
+
+	memset(vpd, 0, len);
+
+	if (adapter)
+		rc = cxl_guest_read_adapter_vpd(adapter, vpd, len);
+	else
+		rc = cxl_guest_read_afu_vpd(afu, vpd, len);
+
+	if (rc > 0) {
+		cxl_dump_debug_buffer(vpd, rc);
+		rc = 0;
+	}
+	return rc;
+}
+
+int cxl_of_read_afu_handle(struct cxl_afu *afu, struct device_node *afu_np)
+{
+	if (read_handle(afu_np, &afu->guest->handle))
+		return -EINVAL;
+	pr_devel("AFU handle: 0x%.16llx\n", afu->guest->handle);
+
+	return 0;
+}
+
+int cxl_of_read_afu_properties(struct cxl_afu *afu, struct device_node *np)
+{
+	int i, len, rc;
+	char *p;
+	const __be32 *prop;
+	u16 device_id, vendor_id;
+	u32 val = 0, class_code;
+
+	/* Properties are read in the same order as listed in PAPR */
+
+	if (cxl_verbose) {
+		pr_info("Dump of the 'ibm,coherent-platform-function' node properties:\n");
+
+		prop = of_get_property(np, "compatible", &len);
+		i = 0;
+		while (i < len) {
+			p = (char *) prop + i;
+			pr_info("compatible: %s\n", p);
+			i += strlen(p) + 1;
+		}
+		read_prop_string(np, "name");
+	}
+
+	rc = read_phys_addr(np, "reg", afu);
+	if (rc)
+		return rc;
+
+	rc = read_phys_addr(np, "assigned-addresses", afu);
+	if (rc)
+		return rc;
+
+	if (afu->psn_phys == 0)
+		afu->psa = false;
+	else
+		afu->psa = true;
+
+	if (cxl_verbose) {
+		read_prop_string(np, "ibm,loc-code");
+		read_prop_string(np, "device_type");
+	}
+
+	read_prop_dword(np, "ibm,#processes", &afu->max_procs_virtualised);
+
+	if (cxl_verbose) {
+		read_prop_dword(np, "ibm,scratchpad-size", &val);
+		read_prop_dword(np, "ibm,programmable", &val);
+		read_prop_string(np, "ibm,phandle");
+		read_vpd(NULL, afu);
+	}
+
+	read_prop_dword(np, "ibm,max-ints-per-process", &afu->guest->max_ints);
+	afu->irqs_max = afu->guest->max_ints;
+
+	prop = read_prop_dword(np, "ibm,min-ints-per-process", &afu->pp_irqs);
+	if (prop) {
+		/* One extra interrupt for the PSL interrupt is already
+		 * included. Remove it now to keep only AFU interrupts and
+		 * match the native case.
+		 */
+		afu->pp_irqs--;
+	}
+
+	if (cxl_verbose) {
+		read_prop_dword(np, "ibm,max-ints", &val);
+		read_prop_dword(np, "ibm,vpd-size", &val);
+	}
+
+	read_prop64_dword(np, "ibm,error-buffer-size", &afu->eb_len);
+	afu->eb_offset = 0;
+
+	if (cxl_verbose)
+		read_prop_dword(np, "ibm,config-record-type", &val);
+
+	read_prop64_dword(np, "ibm,config-record-size", &afu->crs_len);
+	afu->crs_offset = 0;
+
+	read_prop_dword(np, "ibm,#config-records", &afu->crs_num);
+
+	if (cxl_verbose) {
+		for (i = 0; i < afu->crs_num; i++) {
+			rc = cxl_ops->afu_cr_read16(afu, i, PCI_DEVICE_ID,
+						&device_id);
+			if (!rc)
+				pr_info("record %d - device-id: %#x\n",
+					i, device_id);
+			rc = cxl_ops->afu_cr_read16(afu, i, PCI_VENDOR_ID,
+						&vendor_id);
+			if (!rc)
+				pr_info("record %d - vendor-id: %#x\n",
+					i, vendor_id);
+			rc = cxl_ops->afu_cr_read32(afu, i, PCI_CLASS_REVISION,
+						&class_code);
+			if (!rc) {
+				class_code >>= 8;
+				pr_info("record %d - class-code: %#x\n",
+					i, class_code);
+			}
+		}
+
+		read_prop_dword(np, "ibm,function-number", &val);
+		read_prop_dword(np, "ibm,privileged-function", &val);
+		read_prop_dword(np, "vendor-id", &val);
+		read_prop_dword(np, "device-id", &val);
+		read_prop_dword(np, "revision-id", &val);
+		read_prop_dword(np, "class-code", &val);
+		read_prop_dword(np, "subsystem-vendor-id", &val);
+		read_prop_dword(np, "subsystem-id", &val);
+	}
+	/*
+	 * if "ibm,process-mmio" doesn't exist then per-process mmio is
+	 * not supported
+	 */
+	val = 0;
+	prop = read_prop_dword(np, "ibm,process-mmio", &val);
+	if (prop && val == 1)
+		afu->pp_psa = true;
+	else
+		afu->pp_psa = false;
+
+	if (cxl_verbose) {
+		read_prop_dword(np, "ibm,supports-aur", &val);
+		read_prop_dword(np, "ibm,supports-csrp", &val);
+		read_prop_dword(np, "ibm,supports-prr", &val);
+	}
+
+	prop = read_prop_dword(np, "ibm,function-error-interrupt", &val);
+	if (prop)
+		afu->serr_hwirq = val;
+
+	pr_devel("AFU handle: %#llx\n", afu->guest->handle);
+	pr_devel("p2n_phys: %#llx (size %#llx)\n",
+		afu->guest->p2n_phys, afu->guest->p2n_size);
+	pr_devel("psn_phys: %#llx (size %#llx)\n",
+		afu->psn_phys, afu->adapter->ps_size);
+	pr_devel("Max number of processes virtualised=%i\n",
+		afu->max_procs_virtualised);
+	pr_devel("Per-process irqs min=%i, max=%i\n", afu->pp_irqs,
+		 afu->irqs_max);
+	pr_devel("Slice error interrupt=%#lx\n", afu->serr_hwirq);
+
+	return 0;
+}
+
+static int read_adapter_irq_config(struct cxl *adapter, struct device_node *np)
+{
+	const __be32 *ranges;
+	int len, nranges, i;
+	struct irq_avail *cur;
+
+	ranges = of_get_property(np, "interrupt-ranges", &len);
+	if (ranges == NULL || len < (2 * sizeof(int)))
+		return -EINVAL;
+
+	/*
+	 * encoded array of two cells per entry, each cell encoded as
+	 * with encode-int
+	 */
+	nranges = len / (2 * sizeof(int));
+	if (nranges == 0 || (nranges * 2 * sizeof(int)) != len)
+		return -EINVAL;
+
+	adapter->guest->irq_avail = kzalloc(nranges * sizeof(struct irq_avail),
+					    GFP_KERNEL);
+	if (adapter->guest->irq_avail == NULL)
+		return -ENOMEM;
+
+	adapter->guest->irq_base_offset = be32_to_cpu(ranges[0]);
+	for (i = 0; i < nranges; i++) {
+		cur = &adapter->guest->irq_avail[i];
+		cur->offset = be32_to_cpu(ranges[i * 2]);
+		cur->range  = be32_to_cpu(ranges[i * 2 + 1]);
+		cur->bitmap = kcalloc(BITS_TO_LONGS(cur->range),
+				sizeof(*cur->bitmap), GFP_KERNEL);
+		if (cur->bitmap == NULL)
+			goto err;
+		if (cur->offset < adapter->guest->irq_base_offset)
+			adapter->guest->irq_base_offset = cur->offset;
+		if (cxl_verbose)
+			pr_info("available IRQ range: %#lx-%#lx (%lu)\n",
+				cur->offset, cur->offset + cur->range - 1,
+				cur->range);
+	}
+	adapter->guest->irq_nranges = nranges;
+	spin_lock_init(&adapter->guest->irq_alloc_lock);
+
+	return 0;
+err:
+	for (i--; i >= 0; i--) {
+		cur = &adapter->guest->irq_avail[i];
+		kfree(cur->bitmap);
+	}
+	kfree(adapter->guest->irq_avail);
+	adapter->guest->irq_avail = NULL;
+	return -ENOMEM;
+}
+
+int cxl_of_read_adapter_handle(struct cxl *adapter, struct device_node *np)
+{
+	if (read_handle(np, &adapter->guest->handle))
+		return -EINVAL;
+	pr_devel("Adapter handle: 0x%.16llx\n", adapter->guest->handle);
+
+	return 0;
+}
+
+int cxl_of_read_adapter_properties(struct cxl *adapter, struct device_node *np)
+{
+	int rc, len, naddr, i;
+	char *p;
+	const __be32 *prop;
+	u32 val = 0;
+
+	/* Properties are read in the same order as listed in PAPR */
+
+	naddr = of_n_addr_cells(np);
+
+	if (cxl_verbose) {
+		pr_info("Dump of the 'ibm,coherent-platform-facility' node properties:\n");
+
+		read_prop_dword(np, "#address-cells", &val);
+		read_prop_dword(np, "#size-cells", &val);
+
+		prop = of_get_property(np, "compatible", &len);
+		i = 0;
+		while (i < len) {
+			p = (char *) prop + i;
+			pr_info("compatible: %s\n", p);
+			i += strlen(p) + 1;
+		}
+		read_prop_string(np, "name");
+		read_prop_string(np, "model");
+
+		prop = of_get_property(np, "reg", NULL);
+		if (prop) {
+			pr_info("reg: addr:%#llx size:%#x\n",
+				of_read_number(prop, naddr),
+				be32_to_cpu(prop[naddr]));
+		}
+
+		read_prop_string(np, "ibm,loc-code");
+	}
+
+	if ((rc = read_adapter_irq_config(adapter, np)))
+		return rc;
+
+	if (cxl_verbose) {
+		read_prop_string(np, "device_type");
+		read_prop_string(np, "ibm,phandle");
+	}
+
+	prop = read_prop_dword(np, "ibm,caia-version", &val);
+	if (prop) {
+		adapter->caia_major = (val & 0xFF00) >> 8;
+		adapter->caia_minor = val & 0xFF;
+	}
+
+	prop = read_prop_dword(np, "ibm,psl-revision", &val);
+	if (prop)
+		adapter->psl_rev = val;
+
+	prop = read_prop_string(np, "status");
+	if (prop) {
+		adapter->guest->status = kasprintf(GFP_KERNEL, "%s", (char *) prop);
+		if (adapter->guest->status == NULL)
+			return -ENOMEM;
+	}
+
+	prop = read_prop_dword(np, "vendor-id", &val);
+	if (prop)
+		adapter->guest->vendor = val;
+
+	prop = read_prop_dword(np, "device-id", &val);
+	if (prop)
+		adapter->guest->device = val;
+
+	if (cxl_verbose) {
+		read_prop_dword(np, "ibm,privileged-facility", &val);
+		read_prop_dword(np, "revision-id", &val);
+		read_prop_dword(np, "class-code", &val);
+	}
+
+	prop = read_prop_dword(np, "subsystem-vendor-id", &val);
+	if (prop)
+		adapter->guest->subsystem_vendor = val;
+
+	prop = read_prop_dword(np, "subsystem-id", &val);
+	if (prop)
+		adapter->guest->subsystem = val;
+
+	if (cxl_verbose)
+		read_vpd(adapter, NULL);
+
+	return 0;
+}
+
+static int cxl_of_remove(struct platform_device *pdev)
+{
+	struct cxl *adapter;
+	int afu;
+
+	adapter = dev_get_drvdata(&pdev->dev);
+	for (afu = 0; afu < adapter->slices; afu++)
+		cxl_guest_remove_afu(adapter->afu[afu]);
+
+	cxl_guest_remove_adapter(adapter);
+	return 0;
+}
+
+static void cxl_of_shutdown(struct platform_device *pdev)
+{
+	cxl_of_remove(pdev);
+}
+
+int cxl_of_probe(struct platform_device *pdev)
+{
+	struct device_node *np = NULL;
+	struct device_node *afu_np = NULL;
+	struct cxl *adapter = NULL;
+	int ret;
+	int slice, slice_ok;
+
+	pr_devel("in %s\n", __func__);
+
+	np = pdev->dev.of_node;
+	if (np == NULL)
+		return -ENODEV;
+
+	/* init adapter */
+	adapter = cxl_guest_init_adapter(np, pdev);
+	if (IS_ERR(adapter)) {
+		dev_err(&pdev->dev, "guest_init_adapter failed: %li\n", PTR_ERR(adapter));
+		return PTR_ERR(adapter);
+	}
+
+	/* init afu */
+	slice_ok = 0;
+	for (afu_np = NULL, slice = 0; (afu_np = of_get_next_child(np, afu_np)); slice++) {
+		if ((ret = cxl_guest_init_afu(adapter, slice, afu_np)))
+			dev_err(&pdev->dev, "AFU %i failed to initialise: %i\n",
+				slice, ret);
+		else
+			slice_ok++;
+	}
+
+	if (slice_ok == 0) {
+		dev_info(&pdev->dev, "No active AFU");
+		adapter->slices = 0;
+	}
+
+	if (afu_np)
+		of_node_put(afu_np);
+	return 0;
+}
+
+static const struct of_device_id cxl_of_match[] = {
+	{ .compatible = "ibm,coherent-platform-facility",},
+	{},
+};
+MODULE_DEVICE_TABLE(of, cxl_of_match);
+
+struct platform_driver cxl_of_driver = {
+	.driver = {
+		.name = "cxl_of",
+		.of_match_table = cxl_of_match,
+		.owner = THIS_MODULE
+	},
+	.probe = cxl_of_probe,
+	.remove = cxl_of_remove,
+	.shutdown = cxl_of_shutdown,
+};