From: Myron Stowe <myron.stowe@redhat.com>
To: jbarnes@virtuousgeek.org
Cc: linux-pci@vger.kernel.org, linux@arm.linux.org.uk,
vapier@gentoo.org, dhowells@redhat.com,
ysato@users.sourceforge.jp, tony.luck@intel.com,
fenghua.yu@intel.com, monstr@monstr.eu, ralf@linux-mips.org,
benh@kernel.crashing.org, paulus@samba.org, lethal@linux-sh.org,
davem@davemloft.net, cmetcalf@tilera.com, gxt@mprc.pku.edu.cn,
tglx@linutronix.de, mingo@redhat.com, chris@zankel.net,
linux-kernel@vger.kernel.org
Subject: [PATCH -v2 10/16] PCI: Pull PCI 'latency timer' setup up into the core
Date: Fri, 28 Oct 2011 15:48:38 -0600 [thread overview]
Message-ID: <20111028214838.20088.38904.stgit@amt.stowe> (raw)
In-Reply-To: <20111028214726.20088.30551.stgit@amt.stowe>
From: Myron Stowe <mstowe@redhat.com>
The 'latency timer' of PCI devices, both Type 0 and Type 1,
is setup in architecture-specific code [see: 'pcibios_set_master()'].
There are two approaches being taken by all the architectures - check
if the 'latency timer' is currently set between 16 and 255 and if not
bring it within bounds, or, do nothing (and then there is the
gratuitously different PA-RISC implementation).
There is nothing architecture-specific about PCI's 'latency timer' so
this patch pulls its setup functionality up into the PCI core by
creating a generic 'pcibios_set_master()' function using the '__weak'
attribute which can be used by all architectures as a default which,
if necessary, can then be over-ridden by architecture-specific code.
No functional change.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
---
arch/blackfin/include/asm/pci.h | 4 ----
arch/frv/mb93090-mb00/pci-frv.c | 6 ------
arch/frv/mb93090-mb00/pci-frv.h | 2 --
arch/h8300/include/asm/pci.h | 5 -----
arch/mips/pci/pci.c | 6 ------
arch/mn10300/unit-asb2305/pci-asb2305.c | 6 ------
arch/mn10300/unit-asb2305/pci-asb2305.h | 2 --
arch/sh/drivers/pci/pci.c | 6 ------
arch/x86/include/asm/pci_x86.h | 2 --
arch/x86/pci/i386.c | 6 ------
drivers/pci/pci.c | 29 +++++++++++++++++++++++++++++
include/linux/pci.h | 3 +++
12 files changed, 32 insertions(+), 45 deletions(-)
diff --git a/arch/blackfin/include/asm/pci.h b/arch/blackfin/include/asm/pci.h
index 99cae2e..74352c4 100644
--- a/arch/blackfin/include/asm/pci.h
+++ b/arch/blackfin/include/asm/pci.h
@@ -10,10 +10,6 @@
#define PCIBIOS_MIN_IO 0x00001000
#define PCIBIOS_MIN_MEM 0x10000000
-static inline void pcibios_set_master(struct pci_dev *dev)
-{
- /* No special bus mastering setup handling */
-}
static inline void pcibios_penalize_isa_irq(int irq)
{
/* We don't do dynamic PCI IRQ allocation */
diff --git a/arch/frv/mb93090-mb00/pci-frv.c b/arch/frv/mb93090-mb00/pci-frv.c
index 6b4fb28..6a0cd64 100644
--- a/arch/frv/mb93090-mb00/pci-frv.c
+++ b/arch/frv/mb93090-mb00/pci-frv.c
@@ -195,12 +195,6 @@ void __init pcibios_resource_survey(void)
pcibios_assign_resources();
}
-/*
- * If we set up a device for bus mastering, we need to check the latency
- * timer as certain crappy BIOSes forget to set it properly.
- */
-unsigned int pcibios_max_latency = 255;
-
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
diff --git a/arch/frv/mb93090-mb00/pci-frv.h b/arch/frv/mb93090-mb00/pci-frv.h
index f3fe559..089eeba 100644
--- a/arch/frv/mb93090-mb00/pci-frv.h
+++ b/arch/frv/mb93090-mb00/pci-frv.h
@@ -26,8 +26,6 @@ extern unsigned int __nongpreldata pci_probe;
/* pci-frv.c */
-extern unsigned int pcibios_max_latency;
-
void pcibios_resource_survey(void);
/* pci-vdk.c */
diff --git a/arch/h8300/include/asm/pci.h b/arch/h8300/include/asm/pci.h
index cc97620..0b2acaa 100644
--- a/arch/h8300/include/asm/pci.h
+++ b/arch/h8300/include/asm/pci.h
@@ -9,11 +9,6 @@
#define pcibios_assign_all_busses() 0
-static inline void pcibios_set_master(struct pci_dev *dev)
-{
- /* No special bus mastering setup handling */
-}
-
static inline void pcibios_penalize_isa_irq(int irq, int active)
{
/* We don't do dynamic PCI IRQ allocation */
diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
index 33bba7b..a6de9b8 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -204,12 +204,6 @@ static int pcibios_enable_resources(struct pci_dev *dev, int mask)
return 0;
}
-/*
- * If we set up a device for bus mastering, we need to check the latency
- * timer as certain crappy BIOSes forget to set it properly.
- */
-static unsigned int pcibios_max_latency = 255;
-
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
diff --git a/arch/mn10300/unit-asb2305/pci-asb2305.c b/arch/mn10300/unit-asb2305/pci-asb2305.c
index 8e6763e..2b299c4 100644
--- a/arch/mn10300/unit-asb2305/pci-asb2305.c
+++ b/arch/mn10300/unit-asb2305/pci-asb2305.c
@@ -213,12 +213,6 @@ void __init pcibios_resource_survey(void)
pcibios_allocate_resources(1);
}
-/*
- * If we set up a device for bus mastering, we need to check the latency
- * timer as certain crappy BIOSes forget to set it properly.
- */
-unsigned int pcibios_max_latency = 255;
-
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
diff --git a/arch/mn10300/unit-asb2305/pci-asb2305.h b/arch/mn10300/unit-asb2305/pci-asb2305.h
index c3fa294..1194fe4 100644
--- a/arch/mn10300/unit-asb2305/pci-asb2305.h
+++ b/arch/mn10300/unit-asb2305/pci-asb2305.h
@@ -31,8 +31,6 @@ extern unsigned int pci_probe;
/* pci-asb2305.c */
-extern unsigned int pcibios_max_latency;
-
extern void pcibios_resource_survey(void);
/* pci.c */
diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index 194231c..a0c92fd 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -242,12 +242,6 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
return pci_enable_resources(dev, mask);
}
-/*
- * If we set up a device for bus mastering, we need to check and set
- * the latency timer as it may not be properly set.
- */
-static unsigned int pcibios_max_latency = 255;
-
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index 7045267..497c8a3 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -44,8 +44,6 @@ enum pci_bf_sort_state {
/* pci-i386.c */
-extern unsigned int pcibios_max_latency;
-
void pcibios_resource_survey(void);
void pcibios_set_cache_line_size(void);
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 494f2e7..5663bc2 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -253,12 +253,6 @@ void __init pcibios_resource_survey(void)
*/
fs_initcall(pcibios_assign_resources);
-/*
- * If we set up a device for bus mastering, we need to check the latency
- * timer as certain crappy BIOSes forget to set it properly.
- */
-unsigned int pcibios_max_latency = 255;
-
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 466fad6..a50e643 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -88,6 +88,12 @@ enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_PERFORMANCE;
u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
u8 pci_cache_line_size;
+/*
+ * If we set up a device for bus mastering, we need to check the latency
+ * timer as certain BIOSes forget to set it properly.
+ */
+unsigned int pcibios_max_latency = 255;
+
/**
* pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
* @bus: pointer to PCI bus structure to search
@@ -2590,6 +2596,29 @@ static void __pci_set_master(struct pci_dev *dev, bool enable)
}
/**
+ * pcibios_set_master - enable PCI bus-mastering for device dev
+ * @dev: the PCI device to enable
+ *
+ * Enables PCI bus-mastering for the device. This is the default
+ * implementation. Architecture specific implementations can override
+ * this if necessary.
+ */
+void __weak pcibios_set_master(struct pci_dev *dev)
+{
+ u8 lat;
+
+ pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
+ if (lat < 16)
+ lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
+ else if (lat > pcibios_max_latency)
+ lat = pcibios_max_latency;
+ else
+ return;
+ dev_printk(KERN_DEBUG, &dev->dev, "setting latency timer to %d\n", lat);
+ pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
+}
+
+/**
* pci_set_master - enables bus-mastering for device dev
* @dev: the PCI device to enable
*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index abbd8b6..182b93d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -790,8 +790,11 @@ static inline int pci_is_managed(struct pci_dev *pdev)
}
void pci_disable_device(struct pci_dev *dev);
+
+extern unsigned int pcibios_max_latency;
void pci_set_master(struct pci_dev *dev);
void pci_clear_master(struct pci_dev *dev);
+
int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state);
int pci_set_cacheline_size(struct pci_dev *dev);
#define HAVE_PCI_SET_MWI
next prev parent reply other threads:[~2011-10-28 21:49 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-28 21:47 [PATCH -v2 00/16] PCI: Re-factor PCI's 'latency timer' setup Myron Stowe
2011-10-28 21:47 ` [PATCH -v2 01/16] PCI: add declaration for pcibios_set_master() to pci core Myron Stowe
2011-12-05 19:06 ` Jesse Barnes
2011-12-05 20:32 ` Benjamin Herrenschmidt
2011-10-28 21:47 ` [PATCH -v2 02/16] PCI: ARM: convert pcibios_set_master() to a non-inlined function Myron Stowe
2011-10-28 21:47 ` [PATCH -v2 03/16] PCI: IA64: " Myron Stowe
2011-10-28 21:47 ` [PATCH -v2 04/16] PCI: MicroBlaze: " Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 05/16] PCI: PowerPC: " Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 06/16] PCI: SPARC: " Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 07/16] PCI: TILE: " Myron Stowe
2011-10-31 15:27 ` Chris Metcalf
2011-10-28 21:48 ` [PATCH -v2 08/16] PCI: UniCore: " Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 09/16] PCI: Xtensa: " Myron Stowe
2011-10-28 21:48 ` Myron Stowe [this message]
2011-10-28 21:48 ` [PATCH -v2 11/16] PCI: frv: use generic pcibios_set_master() Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 12/16] PCI: MIPS: " Myron Stowe
2011-10-28 21:48 ` [PATCH -v2 13/16] PCI: mn10300: " Myron Stowe
2011-10-28 21:49 ` [PATCH -v2 14/16] PCI: sh: " Myron Stowe
2011-10-28 21:49 ` [PATCH -v2 15/16] PCI: x86: " Myron Stowe
2011-10-28 21:49 ` [PATCH -v2 16/16] PCI: latency timer doesn't apply to PCIe Myron Stowe
2011-10-29 0:46 ` [PATCH -v2 00/16] PCI: Re-factor PCI's 'latency timer' setup Mike Frysinger
2011-10-31 16:08 ` Myron Stowe
2011-10-31 23:14 ` Myron Stowe
2011-11-11 17:59 ` Jesse Barnes
2011-11-15 22:43 ` Benjamin Herrenschmidt
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