linux/pci: reserve io/memory space for bridge

reserve io/memory space for bridge which will be used later
by PCI hotplug.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 4afc4bbb0bc732fbe5c3ac68a6356cc6bcdf0fe2..abb68ef094696e48fb5e574b0bd389b9eac67e3e 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1259,6 +1259,13 @@ running once the system is up.
                                IXP2000 systems where the bus has to be
                                configured a certain way for adjunct CPUs.
 
+       pci_reserve=    [PCI]
+                       Format: [<sbdf>[+IO<size>][+MEM<size>]][,<sbdf>...]
+                       Format of sbdf: [<segment>:]<bus>:<dev>.<func>
+                       Specifies the least reserved io size or memory size
+                       which is assigned to PCI bridge even when no child
+                       pci device exists. This is useful with PCI hotplug.
+
        pcmv=           [HW,PCMCIA] BadgePAD 4
 
        pd.             [PARIDE]

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 0441375b0e31dad9afb46cdcc93b45690f9eb5ff..e0e3b5bf697830d1f265545154c7ae53dde1e6bf 100644 (file)
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -43,6 +43,14 @@ config PCI_IOMULTI
        default y
        help
          Say Y here if you need io multiplexing.
+
+config PCI_RESERVE
+       bool "PCI IO/MEMORY space reserve"
+       depends on PCI
+       default y
+       help
+         Say Y here if you need PCI IO/MEMORY space reserve
+
 config PCI_IOV
        bool "PCI IOV support"
        depends on PCI

diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index ef8b00fc099ba55129bb9d61b5c9026f581318ae..f9a8a01b7d4c03020f9eae3333368fb7cd1fc043 100644 (file)
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -7,6 +7,7 @@ obj-y           += access.o bus.o probe.o remove.o pci.o quirks.o \
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_PCI_GUESTDEV) += guestdev.o
 obj-$(CONFIG_PCI_IOMULTI) += iomulti.o
+obj-$(CONFIG_PCI_RESERVE) += reserve.o
 
 # Build PCI Express stuff if needed
 obj-$(CONFIG_PCIEPORTBUS) += pcie/

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index e152660b7471c9109fe8521c3c4cba329f16461d..e541b4e33af5add7a496d4672d7cb545097b9144 100644 (file)
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -189,3 +189,18 @@ static inline int pci_iov_bus_range(struct pci_bus *bus)
        return 0;
 }
 #endif /* CONFIG_PCI_IOV */
+
+#ifdef CONFIG_PCI_RESERVE
+unsigned long pci_reserve_size_io(struct pci_bus *bus);
+unsigned long pci_reserve_size_mem(struct pci_bus *bus);
+#else
+static inline unsigned long pci_reserve_size_io(struct pci_bus *bus)
+{
+       return 0;
+}
+
+static inline unsigned long pci_reserve_size_mem(struct pci_bus *bus)
+{
+       return 0;
+}
+#endif /* CONFIG_PCI_RESERVE */

diff --git a/drivers/pci/reserve.c b/drivers/pci/reserve.c
new file mode 100644 (file)
index 0000000..827a95e
--- /dev/null
+++ b/drivers/pci/reserve.c
@@ -0,0 +1,143 @@
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright (c) 2009 Isaku Yamahata
+ *                    VA Linux Systems Japan K.K.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+
+#include <asm/setup.h>
+
+static char pci_reserve_param[COMMAND_LINE_SIZE];
+
+/* pci_reserve=        [PCI]
+ * Format: [<sbdf>[+IO<size>][+MEM<size>]][,<sbdf>...]
+ * Format of sbdf: [<segment>:]<bus>:<dev>.<func>
+ */
+static int pci_reserve_parse_size(const char *str,
+                                 unsigned long *io_size,
+                                 unsigned long *mem_size)
+{
+       if (sscanf(str, "io%lx", io_size) == 1 ||
+           sscanf(str, "IO%lx", io_size) == 1)
+               return 0;
+
+       if (sscanf(str, "mem%lx", mem_size) == 1 ||
+           sscanf(str, "MEM%lx", mem_size) == 1)
+               return 0;
+
+       return -EINVAL;
+}
+
+static int pci_reserve_parse_one(const char *str,
+                                int *seg, int *bus, int *dev, int *func,
+                                unsigned long *io_size,
+                                unsigned long *mem_size)
+{
+       char *p;
+
+       *io_size = 0;
+       *mem_size = 0;
+
+       if (sscanf(str, "%x:%x:%x.%x", seg, bus, dev, func) != 4) {
+               *seg = 0;
+               if (sscanf(str, "%x:%x.%x", bus, dev, func) != 3) {
+                       return -EINVAL;
+               }
+       }
+
+       p = strchr(str, '+');
+       if (p == NULL)
+               return -EINVAL;
+       p++;
+       if (pci_reserve_parse_size(p, io_size, mem_size))
+               return -EINVAL;
+
+       p = strchr(str, '+');
+       if (p != NULL) {
+               p++;
+               pci_reserve_parse_size(p, io_size, mem_size);
+       }
+       return 0;
+}
+
+static unsigned long pci_reserve_size(struct pci_bus *pbus, int flags)
+{
+       char *sp;
+       char *ep;
+
+       int seg;
+       int bus;
+       int dev;
+       int func;
+
+       unsigned long io_size;
+       unsigned long mem_size;
+
+       sp = pci_reserve_param;
+
+       do {
+               ep = strchr(sp, ',');
+               if (ep)
+                       *ep = '\0';     /* chomp */
+
+               if (pci_reserve_parse_one(sp, &seg, &bus, &dev, &func,
+                                         &io_size, &mem_size) == 0) {
+                       if (pci_domain_nr(pbus) == seg &&
+                           pbus->number == bus &&
+                           PCI_SLOT(pbus->self->devfn) == dev &&
+                           PCI_FUNC(pbus->self->devfn) == func) {
+                               switch (flags) {
+                               case IORESOURCE_IO:
+                                       return io_size;
+                               case IORESOURCE_MEM:
+                                       return mem_size;
+                               default:
+                                       break;
+                               }
+                       }
+               }
+
+               if (ep) {
+                       *ep = ',';      /* restore chomp'ed ',' for later */
+                       ep++;
+               }
+               sp = ep;
+       } while (ep);
+
+       return 0;
+}
+
+unsigned long pci_reserve_size_io(struct pci_bus *pbus)
+{
+       return pci_reserve_size(pbus, IORESOURCE_IO);
+}
+
+unsigned long pci_reserve_size_mem(struct pci_bus *pbus)
+{
+       return pci_reserve_size(pbus, IORESOURCE_MEM);
+}
+
+static int __init pci_reserve_setup(char *str)
+{
+       if (strlen(str) > sizeof(pci_reserve_param))
+               return 0;
+       strcpy(pci_reserve_param, str);
+       return 1;
+}
+__setup("pci_reserve=", pci_reserve_setup);

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 12cab0682e7a0a66057e2cd6f05c93fe7b903af9..0d2c745e1e6b867e9af2856e2626c165d00f853f 100644 (file)
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -315,7 +315,7 @@ pbus_size_io(struct pci_bus *bus)
 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
        size = (size & 0xff) + ((size & ~0xffUL) << 2);
 #endif
-       size = ROUND_UP(size + size1, 4096);
+       size = ROUND_UP(max(size + size1, pci_reserve_size_io(bus)), 4096);
        if (!size) {
                b_res->flags = 0;
                return;
@@ -393,7 +393,7 @@ pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
                        min_align = align1 >> 1;
                align += aligns[order];
        }
-       size = ROUND_UP(size, min_align);
+       size = ROUND_UP(max(size, pci_reserve_size_mem(bus)), min_align);
        if (!size) {
                b_res->flags = 0;
                return 1;