[RFC PATCH 02/10] s390/pci: CLP interface
From: Jan Glauber
Date: Wed Nov 14 2012 - 04:42:22 EST
CLP instructions are used to query the firmware about detected PCI
functions, the attributes of those functions and to enable or disable
a PCI function. The CLP interface is the equivalent to a PCI bus scan.
Signed-off-by: Jan Glauber <jang@xxxxxxxxxxxxxxxxxx>
---
arch/s390/include/asm/clp.h | 28 ++++
arch/s390/include/asm/pci.h | 7 +
arch/s390/include/asm/pci_clp.h | 182 +++++++++++++++++++++++
arch/s390/pci/Makefile | 2 +-
arch/s390/pci/pci.c | 28 ++++
arch/s390/pci/pci_clp.c | 317 ++++++++++++++++++++++++++++++++++++++++
6 files changed, 563 insertions(+), 1 deletion(-)
create mode 100644 arch/s390/include/asm/clp.h
create mode 100644 arch/s390/include/asm/pci_clp.h
create mode 100644 arch/s390/pci/pci_clp.c
diff --git a/arch/s390/include/asm/clp.h b/arch/s390/include/asm/clp.h
new file mode 100644
index 0000000..6c3aecc
--- /dev/null
+++ b/arch/s390/include/asm/clp.h
@@ -0,0 +1,28 @@
+#ifndef _ASM_S390_CLP_H
+#define _ASM_S390_CLP_H
+
+/* CLP common request & response block size */
+#define CLP_BLK_SIZE (PAGE_SIZE * 2)
+
+struct clp_req_hdr {
+ u16 len;
+ u16 cmd;
+} __packed;
+
+struct clp_rsp_hdr {
+ u16 len;
+ u16 rsp;
+} __packed;
+
+/* CLP Response Codes */
+#define CLP_RC_OK 0x0010 /* Command request successfully */
+#define CLP_RC_CMD 0x0020 /* Command code not recognized */
+#define CLP_RC_PERM 0x0030 /* Command not authorized */
+#define CLP_RC_FMT 0x0040 /* Invalid command request format */
+#define CLP_RC_LEN 0x0050 /* Invalid command request length */
+#define CLP_RC_8K 0x0060 /* Command requires 8K LPCB */
+#define CLP_RC_RESNOT0 0x0070 /* Reserved field not zero */
+#define CLP_RC_NODATA 0x0080 /* No data available */
+#define CLP_RC_FC_UNKNOWN 0x0100 /* Function code not recognized */
+
+#endif
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 5e286ce..079b7e2 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -8,6 +8,7 @@
#include <asm-generic/pci.h>
#include <asm-generic/pci-dma-compat.h>
+#include <asm/pci_clp.h>
#define PCIBIOS_MIN_IO 0x1000
#define PCIBIOS_MIN_MEM 0x10000000
@@ -76,6 +77,12 @@ void zpci_stop_device(struct zpci_dev *);
void zpci_free_device(struct zpci_dev *);
int zpci_scan_device(struct zpci_dev *);
+/* CLP */
+int clp_find_pci_devices(void);
+int clp_add_pci_device(u32, u32, int);
+int clp_enable_fh(struct zpci_dev *, u8);
+int clp_disable_fh(struct zpci_dev *);
+
/* Helpers */
struct zpci_dev *get_zdev(struct pci_dev *);
struct zpci_dev *get_zdev_by_fid(u32);
diff --git a/arch/s390/include/asm/pci_clp.h b/arch/s390/include/asm/pci_clp.h
new file mode 100644
index 0000000..e97163e
--- /dev/null
+++ b/arch/s390/include/asm/pci_clp.h
@@ -0,0 +1,182 @@
+#ifndef _ASM_S390_PCI_CLP_H
+#define _ASM_S390_PCI_CLP_H
+
+#include <asm/clp.h>
+
+/*
+ * Call Logical Processor - Command Codes
+ */
+#define CLP_LIST_PCI 0x0002
+#define CLP_QUERY_PCI_FN 0x0003
+#define CLP_QUERY_PCI_FNGRP 0x0004
+#define CLP_SET_PCI_FN 0x0005
+
+/* PCI function handle list entry */
+struct clp_fh_list_entry {
+ u16 device_id;
+ u16 vendor_id;
+ u32 config_state : 1;
+ u32 : 31;
+ u32 fid; /* PCI function id */
+ u32 fh; /* PCI function handle */
+} __packed;
+
+#define CLP_RC_SETPCIFN_FH 0x0101 /* Invalid PCI fn handle */
+#define CLP_RC_SETPCIFN_FHOP 0x0102 /* Fn handle not valid for op */
+#define CLP_RC_SETPCIFN_DMAAS 0x0103 /* Invalid DMA addr space */
+#define CLP_RC_SETPCIFN_RES 0x0104 /* Insufficient resources */
+#define CLP_RC_SETPCIFN_ALRDY 0x0105 /* Fn already in requested state */
+#define CLP_RC_SETPCIFN_ERR 0x0106 /* Fn in permanent error state */
+#define CLP_RC_SETPCIFN_RECPND 0x0107 /* Error recovery pending */
+#define CLP_RC_SETPCIFN_BUSY 0x0108 /* Fn busy */
+#define CLP_RC_LISTPCI_BADRT 0x010a /* Resume token not recognized */
+#define CLP_RC_QUERYPCIFG_PFGID 0x010b /* Unrecognized PFGID */
+
+/* request or response block header length */
+#define LIST_PCI_HDR_LEN 32
+
+/* Number of function handles fitting in response block */
+#define CLP_FH_LIST_NR_ENTRIES \
+ ((CLP_BLK_SIZE - 2 * LIST_PCI_HDR_LEN) \
+ / sizeof(struct clp_fh_list_entry))
+
+#define CLP_SET_ENABLE_PCI_FN 0 /* Yes, 0 enables it */
+#define CLP_SET_DISABLE_PCI_FN 1 /* Yes, 1 disables it */
+
+#define CLP_UTIL_STR_LEN 64
+
+/* List PCI functions request */
+struct clp_req_list_pci {
+ struct clp_req_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u64 resume_token;
+ u64 reserved2;
+} __packed;
+
+/* List PCI functions response */
+struct clp_rsp_list_pci {
+ struct clp_rsp_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u64 resume_token;
+ u32 reserved2;
+ u16 max_fn;
+ u8 reserved3;
+ u8 entry_size;
+ struct clp_fh_list_entry fh_list[CLP_FH_LIST_NR_ENTRIES];
+} __packed;
+
+/* Query PCI function request */
+struct clp_req_query_pci {
+ struct clp_req_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u32 fh; /* function handle */
+ u32 reserved2;
+ u64 reserved3;
+} __packed;
+
+/* Query PCI function response */
+struct clp_rsp_query_pci {
+ struct clp_rsp_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u16 vfn; /* virtual fn number */
+ u16 : 7;
+ u16 util_str_avail : 1; /* utility string available? */
+ u16 pfgid : 8; /* pci function group id */
+ u32 fid; /* pci function id */
+ u8 bar_size[PCI_BAR_COUNT];
+ u16 pchid;
+ u32 bar[PCI_BAR_COUNT];
+ u64 reserved2;
+ u64 sdma; /* start dma as */
+ u64 edma; /* end dma as */
+ u64 reserved3[6];
+ u8 util_str[CLP_UTIL_STR_LEN]; /* utility string */
+} __packed;
+
+/* Query PCI function group request */
+struct clp_req_query_pci_grp {
+ struct clp_req_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u32 : 24;
+ u32 pfgid : 8; /* function group id */
+ u32 reserved2;
+ u64 reserved3;
+} __packed;
+
+/* Query PCI function group response */
+struct clp_rsp_query_pci_grp {
+ struct clp_rsp_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u16 : 4;
+ u16 noi : 12; /* number of interrupts */
+ u8 version;
+ u8 : 6;
+ u8 frame : 1;
+ u8 refresh : 1; /* TLB refresh mode */
+ u16 reserved2;
+ u16 mui;
+ u64 reserved3;
+ u64 dasm; /* dma address space mask */
+ u64 msia; /* MSI address */
+ u64 reserved4;
+ u64 reserved5;
+} __packed;
+
+/* Set PCI function request */
+struct clp_req_set_pci {
+ struct clp_req_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u32 fh; /* function handle */
+ u16 reserved2;
+ u8 oc; /* operation controls */
+ u8 ndas; /* number of dma spaces */
+ u64 reserved3;
+} __packed;
+
+/* Set PCI function response */
+struct clp_rsp_set_pci {
+ struct clp_rsp_hdr hdr;
+ u32 fmt : 4; /* cmd request block format */
+ u32 : 28;
+ u64 reserved1;
+ u32 fh; /* function handle */
+ u32 reserved3;
+ u64 reserved4;
+} __packed;
+
+/* Combined request/response block structures used by clp insn */
+struct clp_req_rsp_list_pci {
+ struct clp_req_list_pci request;
+ struct clp_rsp_list_pci response;
+} __packed;
+
+struct clp_req_rsp_set_pci {
+ struct clp_req_set_pci request;
+ struct clp_rsp_set_pci response;
+} __packed;
+
+struct clp_req_rsp_query_pci {
+ struct clp_req_query_pci request;
+ struct clp_rsp_query_pci response;
+} __packed;
+
+struct clp_req_rsp_query_pci_grp {
+ struct clp_req_query_pci_grp request;
+ struct clp_rsp_query_pci_grp response;
+} __packed;
+
+#endif
diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile
index 78a1344..1afd68c 100644
--- a/arch/s390/pci/Makefile
+++ b/arch/s390/pci/Makefile
@@ -2,4 +2,4 @@
# Makefile for the s390 PCI subsystem.
#
-obj-$(CONFIG_PCI) += pci.o
+obj-$(CONFIG_PCI) += pci.o pci_clp.o
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 0b80ac7..70f6c56 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -29,6 +29,7 @@
#include <asm/facility.h>
#include <asm/pci_insn.h>
+#include <asm/pci_clp.h>
#define DEBUG /* enable pr_debug */
@@ -436,6 +437,20 @@ static void zpci_free_domain(struct zpci_dev *zdev)
spin_unlock(&zpci_domain_lock);
}
+int zpci_enable_device(struct zpci_dev *zdev)
+{
+ int rc;
+
+ rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
+ if (rc)
+ goto out;
+ pr_info("Enabled fh: 0x%x fid: 0x%x\n", zdev->fh, zdev->fid);
+ return 0;
+out:
+ return rc;
+}
+EXPORT_SYMBOL_GPL(zpci_enable_device);
+
int zpci_create_device(struct zpci_dev *zdev)
{
int rc;
@@ -455,8 +470,15 @@ int zpci_create_device(struct zpci_dev *zdev)
if (zdev->state == ZPCI_FN_STATE_STANDBY)
return 0;
+ rc = zpci_enable_device(zdev);
+ if (rc)
+ goto out_start;
return 0;
+out_start:
+ mutex_lock(&zpci_list_lock);
+ list_del(&zdev->entry);
+ mutex_unlock(&zpci_list_lock);
out_bus:
zpci_free_domain(zdev);
out:
@@ -489,6 +511,7 @@ int zpci_scan_device(struct zpci_dev *zdev)
return 0;
out:
+ clp_disable_fh(zdev);
return -EIO;
}
EXPORT_SYMBOL_GPL(zpci_scan_device);
@@ -547,9 +570,14 @@ static int __init pci_base_init(void)
if (rc)
goto out_mem;
+ rc = clp_find_pci_devices();
+ if (rc)
+ goto out_find;
+
zpci_scan_devices();
return 0;
+out_find:
zpci_mem_exit();
out_mem:
return rc;
diff --git a/arch/s390/pci/pci_clp.c b/arch/s390/pci/pci_clp.c
new file mode 100644
index 0000000..291da1a
--- /dev/null
+++ b/arch/s390/pci/pci_clp.c
@@ -0,0 +1,317 @@
+/*
+ * Copyright IBM Corp. 2012
+ *
+ * Author(s):
+ * Jan Glauber <jang@xxxxxxxxxxxxxxxxxx>
+ */
+
+#define COMPONENT "zPCI"
+#define pr_fmt(fmt) COMPONENT ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <asm/pci_clp.h>
+
+/*
+ * Call Logical Processor
+ * Retry logic is handled by the caller.
+ */
+static inline u8 clp_instr(void *req)
+{
+ u64 ilpm;
+ u8 cc;
+
+ asm volatile (
+ " .insn rrf,0xb9a00000,%[ilpm],%[req],0x0,0x2\n"
+ " ipm %[cc]\n"
+ " srl %[cc],28\n"
+ : [cc] "=d" (cc), [ilpm] "=d" (ilpm)
+ : [req] "a" (req)
+ : "cc", "memory");
+ return cc;
+}
+
+static void *clp_alloc_block(void)
+{
+ struct page *page = alloc_pages(GFP_KERNEL, get_order(CLP_BLK_SIZE));
+ return (page) ? page_address(page) : NULL;
+}
+
+static void clp_free_block(void *ptr)
+{
+ free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
+}
+
+static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
+ struct clp_rsp_query_pci_grp *response)
+{
+ switch (response->version) {
+ case 1:
+ zdev->max_bus_speed = PCIE_SPEED_5_0GT;
+ break;
+ default:
+ zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
+ break;
+ }
+}
+
+static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
+{
+ struct clp_req_rsp_query_pci_grp *rrb;
+ int rc;
+
+ rrb = clp_alloc_block();
+ if (!rrb)
+ return -ENOMEM;
+
+ memset(rrb, 0, sizeof(*rrb));
+ rrb->request.hdr.len = sizeof(rrb->request);
+ rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
+ rrb->response.hdr.len = sizeof(rrb->response);
+ rrb->request.pfgid = pfgid;
+
+ rc = clp_instr(rrb);
+ if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
+ clp_store_query_pci_fngrp(zdev, &rrb->response);
+ else {
+ pr_err("Query PCI FNGRP failed with response: %x cc: %d\n",
+ rrb->response.hdr.rsp, rc);
+ rc = -EIO;
+ }
+ clp_free_block(rrb);
+ return rc;
+}
+
+static int clp_store_query_pci_fn(struct zpci_dev *zdev,
+ struct clp_rsp_query_pci *response)
+{
+ int i;
+
+ for (i = 0; i < PCI_BAR_COUNT; i++) {
+ zdev->bars[i].val = le32_to_cpu(response->bar[i]);
+ zdev->bars[i].size = response->bar_size[i];
+ }
+ zdev->pchid = response->pchid;
+ zdev->pfgid = response->pfgid;
+ return 0;
+}
+
+static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
+{
+ struct clp_req_rsp_query_pci *rrb;
+ int rc;
+
+ rrb = clp_alloc_block();
+ if (!rrb)
+ return -ENOMEM;
+
+ memset(rrb, 0, sizeof(*rrb));
+ rrb->request.hdr.len = sizeof(rrb->request);
+ rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
+ rrb->response.hdr.len = sizeof(rrb->response);
+ rrb->request.fh = fh;
+
+ rc = clp_instr(rrb);
+ if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
+ rc = clp_store_query_pci_fn(zdev, &rrb->response);
+ if (rc)
+ goto out;
+ if (rrb->response.pfgid)
+ rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
+ } else {
+ pr_err("Query PCI failed with response: %x cc: %d\n",
+ rrb->response.hdr.rsp, rc);
+ rc = -EIO;
+ }
+out:
+ clp_free_block(rrb);
+ return rc;
+}
+
+int clp_add_pci_device(u32 fid, u32 fh, int configured)
+{
+ struct zpci_dev *zdev;
+ int rc;
+
+ zdev = zpci_alloc_device();
+ if (IS_ERR(zdev))
+ return PTR_ERR(zdev);
+
+ zdev->fh = fh;
+ zdev->fid = fid;
+
+ /* Query function properties and update zdev */
+ rc = clp_query_pci_fn(zdev, fh);
+ if (rc)
+ goto error;
+
+ if (configured)
+ zdev->state = ZPCI_FN_STATE_CONFIGURED;
+ else
+ zdev->state = ZPCI_FN_STATE_STANDBY;
+
+ rc = zpci_create_device(zdev);
+ if (rc)
+ goto error;
+ return 0;
+
+error:
+ zpci_free_device(zdev);
+ return rc;
+}
+
+/*
+ * Enable/Disable a given PCI function defined by its function handle.
+ */
+static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
+{
+ struct clp_req_rsp_set_pci *rrb;
+ int rc, retries = 1000;
+
+ rrb = clp_alloc_block();
+ if (!rrb)
+ return -ENOMEM;
+
+ do {
+ memset(rrb, 0, sizeof(*rrb));
+ rrb->request.hdr.len = sizeof(rrb->request);
+ rrb->request.hdr.cmd = CLP_SET_PCI_FN;
+ rrb->response.hdr.len = sizeof(rrb->response);
+ rrb->request.fh = *fh;
+ rrb->request.oc = command;
+ rrb->request.ndas = nr_dma_as;
+
+ rc = clp_instr(rrb);
+ if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
+ retries--;
+ if (retries < 0)
+ break;
+ msleep(1);
+ }
+ } while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
+
+ if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
+ *fh = rrb->response.fh;
+ else {
+ pr_err("Set PCI FN failed with response: %x cc: %d\n",
+ rrb->response.hdr.rsp, rc);
+ rc = -EIO;
+ }
+ clp_free_block(rrb);
+ return rc;
+}
+
+int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
+{
+ u32 fh = zdev->fh;
+ int rc;
+
+ rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
+ if (!rc)
+ /* Success -> store enabled handle in zdev */
+ zdev->fh = fh;
+ return rc;
+}
+
+int clp_disable_fh(struct zpci_dev *zdev)
+{
+ u32 fh = zdev->fh;
+ int rc;
+
+ if (!zdev_enabled(zdev))
+ return 0;
+
+ dev_info(&zdev->pdev->dev, "disabling fn handle: 0x%x\n", fh);
+ rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
+ if (!rc)
+ /* Success -> store disabled handle in zdev */
+ zdev->fh = fh;
+ else
+ dev_err(&zdev->pdev->dev,
+ "Failed to disable fn handle: 0x%x\n", fh);
+ return rc;
+}
+
+static void clp_check_pcifn_entry(struct clp_fh_list_entry *entry)
+{
+ int present, rc;
+
+ if (!entry->vendor_id)
+ return;
+
+ /* TODO: be a little bit more scalable */
+ present = zpci_fid_present(entry->fid);
+
+ if (present)
+ pr_debug("%s: device %x already present\n", __func__, entry->fid);
+
+ /* skip already used functions */
+ if (present && entry->config_state)
+ return;
+
+ /* aev 306: function moved to stand-by state */
+ if (present && !entry->config_state) {
+ /*
+ * The handle is already disabled, that means no iota/irq freeing via
+ * the firmware interfaces anymore. Need to free resources manually
+ * (DMA memory, debug, sysfs)...
+ */
+ zpci_stop_device(get_zdev_by_fid(entry->fid));
+ return;
+ }
+
+ rc = clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
+ if (rc)
+ pr_err("Failed to add fid: 0x%x\n", entry->fid);
+}
+
+int clp_find_pci_devices(void)
+{
+ struct clp_req_rsp_list_pci *rrb;
+ u64 resume_token = 0;
+ int entries, i, rc;
+
+ rrb = clp_alloc_block();
+ if (!rrb)
+ return -ENOMEM;
+
+ do {
+ memset(rrb, 0, sizeof(*rrb));
+ rrb->request.hdr.len = sizeof(rrb->request);
+ rrb->request.hdr.cmd = CLP_LIST_PCI;
+ /* store as many entries as possible */
+ rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
+ rrb->request.resume_token = resume_token;
+
+ /* Get PCI function handle list */
+ rc = clp_instr(rrb);
+ if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
+ pr_err("List PCI failed with response: 0x%x cc: %d\n",
+ rrb->response.hdr.rsp, rc);
+ rc = -EIO;
+ goto out;
+ }
+
+ WARN_ON_ONCE(rrb->response.entry_size !=
+ sizeof(struct clp_fh_list_entry));
+
+ entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
+ rrb->response.entry_size;
+ pr_info("Detected number of PCI functions: %u\n", entries);
+
+ /* Store the returned resume token as input for the next call */
+ resume_token = rrb->response.resume_token;
+
+ for (i = 0; i < entries; i++)
+ clp_check_pcifn_entry(&rrb->response.fh_list[i]);
+ } while (resume_token);
+
+ pr_debug("Maximum number of supported PCI functions: %u\n",
+ rrb->response.max_fn);
+out:
+ clp_free_block(rrb);
+ return rc;
+}
--
1.7.12.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/