[RFC PATCH 2/2] arm: pcibios: move to generic PCI domains

Lorenzo Pieralisi lorenzo.pieralisi at arm.com
Thu Oct 30 04:44:48 PDT 2014


Most if not all ARM PCI host controller device drivers either ignore the
domain field in the pci_sys_data structure or just increment it every
time a host controller is probed, using it as a domain counter.

Therefore, instead of relying on pci_sys_data to stash the domain number
in a standard location, ARM pcibios code can be moved to the newly
introduced generic PCI domains code, implemented in commits:

commit 41e5c0f81d3e676d671d96a0a1fafb27abfbd9
("of/pci: Add pci_get_new_domain_nr() and of_get_pci_domain_nr()")

commit 670ba0c8883b576d0aec28bd7a838358a4be1
("PCI: Add generic domain handling")

In order to assign a domain number dynamically, the ARM pcibios defines
the function, called by core PCI code:

void pci_bus_assign_domain_nr(...)

that relies on a DT property to define the domain number or falls back to
a counter; its usage replaces the current domain assignment code in PCI
host controllers present in the kernel.

Cc: Arnd Bergmann <arnd at arndb.de>
Cc: Phil Edworthy <phil.edworthy at renesas.com>
Cc: Jason Gunthorpe <jgunthorpe at obsidianresearch.com>
Cc: Jingoo Han <jg1.han at samsung.com>
Cc: Bjorn Helgaas <bhelgaas at google.com>
Cc: Russell King <linux at arm.linux.org.uk>
Cc: Mohit Kumar <mohit.kumar at st.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
---
 arch/arm/Kconfig                   |  3 +++
 arch/arm/include/asm/mach/pci.h    |  3 ---
 arch/arm/include/asm/pci.h         |  7 -------
 arch/arm/kernel/bios32.c           | 26 +++++++++++++++++++++++---
 drivers/pci/host/pci-mvebu.c       | 10 ++--------
 drivers/pci/host/pcie-designware.c |  3 ---
 drivers/pci/host/pcie-rcar.c       |  3 ---
 7 files changed, 28 insertions(+), 27 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 89c4b5c..29544f0 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1292,6 +1292,9 @@ config PCI_DOMAINS
 	bool
 	depends on PCI
 
+config PCI_DOMAINS_GENERIC
+	def_bool PCI_DOMAINS
+
 config PCI_NANOENGINE
 	bool "BSE nanoEngine PCI support"
 	depends on SA1100_NANOENGINE
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 7fc4278..f19f627 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h
@@ -44,9 +44,6 @@ struct hw_pci {
  * Per-controller structure
  */
 struct pci_sys_data {
-#ifdef CONFIG_PCI_DOMAINS
-	int		domain;
-#endif
 	struct list_head node;
 	int		busnr;		/* primary bus number			*/
 	u64		mem_offset;	/* bus->cpu memory mapping offset	*/
diff --git a/arch/arm/include/asm/pci.h b/arch/arm/include/asm/pci.h
index 7e95d85..585dc33 100644
--- a/arch/arm/include/asm/pci.h
+++ b/arch/arm/include/asm/pci.h
@@ -18,13 +18,6 @@ static inline int pcibios_assign_all_busses(void)
 }
 
 #ifdef CONFIG_PCI_DOMAINS
-static inline int pci_domain_nr(struct pci_bus *bus)
-{
-	struct pci_sys_data *root = bus->sysdata;
-
-	return root->domain;
-}
-
 static inline int pci_proc_domain(struct pci_bus *bus)
 {
 	return pci_domain_nr(bus);
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 17a26c1..d8c2b4e 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -11,6 +11,8 @@
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
 
 #include <asm/mach-types.h>
 #include <asm/mach/map.h>
@@ -468,9 +470,6 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
 		if (!sys)
 			panic("PCI: unable to allocate sys data!");
 
-#ifdef CONFIG_PCI_DOMAINS
-		sys->domain  = hw->domain;
-#endif
 		sys->busnr   = busnr;
 		sys->swizzle = hw->swizzle;
 		sys->map_irq = hw->map_irq;
@@ -511,6 +510,27 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
 	}
 }
 
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+static bool dt_domain_found;
+
+void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
+{
+	int domain = of_get_pci_domain_nr(parent->of_node);
+
+	if (domain >= 0) {
+		dt_domain_found = true;
+	} else if (dt_domain_found == true) {
+		dev_err(parent, "Node %s is missing \"linux,pci-domain\" property in DT\n",
+			parent->of_node->full_name);
+		return;
+	} else {
+		domain = pci_get_new_domain_nr();
+	}
+
+	bus->domain_nr = domain;
+}
+#endif
+
 void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
 {
 	struct pci_sys_data *sys;
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index b1315e1..2b4c1f2 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -722,17 +722,11 @@ static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
 {
 	struct mvebu_pcie *pcie = sys_to_pcie(sys);
 	int i;
-	int domain = 0;
 
-#ifdef CONFIG_PCI_DOMAINS
-	domain = sys->domain;
-#endif
-
-	snprintf(pcie->mem_name, sizeof(pcie->mem_name), "PCI MEM %04x",
-		 domain);
+	snprintf(pcie->mem_name, sizeof(pcie->mem_name), "PCI MEM %04x", nr);
 	pcie->mem.name = pcie->mem_name;
 
-	snprintf(pcie->io_name, sizeof(pcie->io_name), "PCI I/O %04x", domain);
+	snprintf(pcie->io_name, sizeof(pcie->io_name), "PCI I/O %04x", nr);
 	pcie->realio.name = pcie->io_name;
 
 	if (request_resource(&iomem_resource, &pcie->mem))
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index dfed00a..6790b87 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -502,9 +502,6 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
 	dw_pci.private_data = (void **)&pp;
 
 	pci_common_init_dev(pp->dev, &dw_pci);
-#ifdef CONFIG_PCI_DOMAINS
-	dw_pci.domain++;
-#endif
 
 	return 0;
 }
diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index 61158e0..b6b859e 100644
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c
@@ -404,9 +404,6 @@ static void rcar_pcie_enable(struct rcar_pcie *pcie)
 	rcar_pci.private_data = (void **)&pcie;
 
 	pci_common_init_dev(&pdev->dev, &rcar_pci);
-#ifdef CONFIG_PCI_DOMAINS
-	rcar_pci.domain++;
-#endif
 }
 
 static int phy_wait_for_ack(struct rcar_pcie *pcie)
-- 
2.1.2




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