Re: [PATCH v2 2/8] PCI: designware: refactor host init code to re-use on v3.65 DW pci hw

From: Murali Karicheri
Date: Fri Jun 20 2014 - 14:49:55 EST


On 6/18/2014 3:05 AM, Pratyush Anand wrote:
Hi Murali,

On Wed, Jun 11, 2014 at 02:51:21AM +0800, Murali Karicheri wrote:
Current DW PCI host init code has code specific to newer hw such as
ATU port specific resource parsing and map. v3.65 DW PCI host has
OK, Older version did not had standard viewport implementation, so patch 1
of this series will help you to take care for that.

MSI controller in application space and requires different controller
Since MSI controller is implemented in application space, so this may
not be same for different older version dw controller users.

Therefore, I would suggest to implement all application specific code
in your keystone driver only.
Pratyush,

Thanks for the comments.

This is IP specific code and another driver that has this version of the IP will be able to
re-use the code. This is also being discussed in another thread from Bjorn and Jingoo.
Please discuss this in that thread.

initialization code. So refactor the msi host controller code into a
separate function. Other common functions across both hw versions
are moved to dw_pcie_common_host_init() and called from the newer and
v3.65 hw host initialization code.

Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx>

CC: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
CC: Russell King <linux@xxxxxxxxxxxxxxxx>
CC: Grant Likely <grant.likely@xxxxxxxxxx>
CC: Rob Herring <robh+dt@xxxxxxxxxx>
CC: Mohit Kumar <mohit.kumar@xxxxxx>
CC: Jingoo Han <jg1.han@xxxxxxxxxxx>
CC: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
CC: Pratyush Anand <pratyush.anand@xxxxxx>
CC: Richard Zhu <r65037@xxxxxxxxxxxxx>
CC: Kishon Vijay Abraham I <kishon@xxxxxx>
CC: Marek Vasut <marex@xxxxxxx>
CC: Arnd Bergmann <arnd@xxxxxxxx>
CC: Pawel Moll <pawel.moll@xxxxxxx>
CC: Mark Rutland <mark.rutland@xxxxxxx>
CC: Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx>
CC: Kumar Gala <galak@xxxxxxxxxxxxxx>
CC: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
CC: Grant Likely <grant.likely@xxxxxxxxxx>

---
drivers/pci/host/pcie-designware.c | 136 ++++++++++++++++++++++++++----------
1 file changed, 101 insertions(+), 35 deletions(-)

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index e8f5d8d..e4bd19a 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -389,13 +389,19 @@ static const struct irq_domain_ops msi_domain_ops = {
.map = dw_pcie_msi_map,
};
-int __init dw_pcie_host_init(struct pcie_port *pp)
+/*
+ * dw_pcie_parse_resource() - Function to parse common resources
+ *
+ * @pp: ptr to pcie port
+ *
+ * Parse the range property for MEM, IO and cfg resources, and map
+ * the cfg register space.
+ */
Why do you need this function? If you have some extra resource, you
can ioremap that before you call dw_pcie_host_init.

I assume you are referring to dw_pcie_parse_resource(). Keystone PCIe driver needs
this to parse the range property for IORESOURCE_MEM and IORESOURCE_IO resources.
So refactored this into a function and called from host_init()
code for v3.65 and dw_pcie_host_init . But for Keystone PCI driver, no need to ioremap
cfg1 and cfg2 as it doesn't have ATU ports. So host_init() code has to be little different.
Idea is to have IP specific host_init() and refactor and re-use the common code on both.


+int __init dw_pcie_parse_resource(struct pcie_port *pp)
{
struct device_node *np = pp->dev->of_node;
struct of_pci_range range;
struct of_pci_range_parser parser;
- u32 val;
- int i;
if (of_pci_range_parser_init(&parser, np)) {
dev_err(pp->dev, "missing ranges property\n");
@@ -431,41 +437,29 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
pp->config.cfg1_size = resource_size(&pp->cfg)/2;
}
}
-
- if (!pp->dbi_base) {
- pp->dbi_base = devm_ioremap(pp->dev, pp->cfg.start,
- resource_size(&pp->cfg));
- if (!pp->dbi_base) {
- dev_err(pp->dev, "error with ioremap\n");
- return -ENOMEM;
- }
- }
-
- pp->cfg0_base = pp->cfg.start;
- pp->cfg1_base = pp->cfg.start + pp->config.cfg0_size;
pp->mem_base = pp->mem.start;
- pp->va_cfg0_base = devm_ioremap(pp->dev, pp->cfg0_base,
- pp->config.cfg0_size);
- if (!pp->va_cfg0_base) {
- dev_err(pp->dev, "error with ioremap in function\n");
- return -ENOMEM;
- }
- pp->va_cfg1_base = devm_ioremap(pp->dev, pp->cfg1_base,
- pp->config.cfg1_size);
- if (!pp->va_cfg1_base) {
- dev_err(pp->dev, "error with ioremap\n");
- return -ENOMEM;
- }
+ return 0;
+}
- if (of_property_read_u32(np, "num-lanes", &pp->lanes)) {
- dev_err(pp->dev, "Failed to parse the number of lanes\n");
- return -EINVAL;
- }
+/*
+ * dw_pcie_msi_host_init() - Function to initialize msi host controller
+ *
+ * @pp: ptr to pcie port
+ * @np: device node ptr to msi irq controller
+ * @irq_msi_ops: ptr to MSI irq_domain_ops struct
+ *
+ * Function register irq domain for msi irq controller and create mappings
+ * for MSI irqs.
+ */

May be you can only do following to support your MSI chip:

Initialize pp->irq_domain into your add_pcie_port function before you
call dw_pcie_host_init.

In dw_pcie_host_init,

if (IS_ENABLED(CONFIG_PCI_MSI) && !pp->irq_domain)

How do I pass the keystone specific msi irq_domain_ops? It looks clean the way it is implemented
in this patch. Also since MSI host controller and legacy host controller are different, it make
sense to add separate host_init for each. Let me know.

Regards,

Murali


+int dw_pcie_msi_host_init(struct pcie_port *pp, struct device_node *np,
+ const struct irq_domain_ops *irq_msi_ops)
+{
+ int i;
if (IS_ENABLED(CONFIG_PCI_MSI)) {
pp->irq_domain = irq_domain_add_linear(pp->dev->of_node,
- MAX_MSI_IRQS, &msi_domain_ops,
+ MAX_MSI_IRQS, irq_msi_ops,
&dw_pcie_msi_chip);
if (!pp->irq_domain) {
dev_err(pp->dev, "irq domain init failed\n");
@@ -476,6 +470,29 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
irq_create_mapping(pp->irq_domain, i);
}
+ return 0;
+}
+
+/*
+ * dw_pcie_common_host_init() - common host init function across different
+ * versions of the designware PCI controller.
+ * @pp: ptr to pcie port
+ * @hw: ptr to hw_pci structure
+ *
+ * This functions parses common DT properties, call host_init() callback
+ * of the PCI controller driver. Also initialize the common RC configurations
+ * and call common pci core function to intialize the controller driver.
+ */
+int __init dw_pcie_common_host_init(struct pcie_port *pp, struct hw_pci *hw)
+{
+ struct device_node *np = pp->dev->of_node;
+ u32 val;
+
+ if (of_property_read_u32(np, "num-lanes", &pp->lanes)) {
+ dev_err(pp->dev, "Failed to parse the number of lanes\n");
+ return -EINVAL;
+ }
+
if (pp->ops->host_init)
pp->ops->host_init(pp);
@@ -488,10 +505,10 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
val |= PORT_LOGIC_SPEED_CHANGE;
dw_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val);
- dw_pci.nr_controllers = 1;
- dw_pci.private_data = (void **)&pp;
+ hw->nr_controllers = 1;
+ hw->private_data = (void **)&pp;
- pci_common_init_dev(pp->dev, &dw_pci);
+ pci_common_init_dev(pp->dev, hw);
pci_assign_unassigned_resources();
#ifdef CONFIG_PCI_DOMAINS
dw_pci.domain++;
@@ -500,6 +517,55 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
return 0;
}
+/*
+ * dw_pcie_host_init() - Host init function for new designware h/w
+ *
+ * @pp: ptr to pcie port
+ *
+ * The function parse the PCI resurces for IO, Memory and map the config
+ * space addresses. Also initliaze the MSI irq controller and call
+ * dw_pcie_common_host_init() to initialize the PCI controller.
+ */
+int __init dw_pcie_host_init(struct pcie_port *pp)
+{
+ int ret;
+
+ ret = dw_pcie_parse_resource(pp);
+ if (ret)
+ return ret;
+
+ if (!pp->dbi_base) {
+ pp->dbi_base = devm_ioremap(pp->dev, pp->cfg.start,
+ resource_size(&pp->cfg));
+ if (!pp->dbi_base) {
+ dev_err(pp->dev, "error with ioremap\n");
+ return -ENOMEM;
+ }
+ }
+
+ pp->cfg0_base = pp->cfg.start;
+ pp->cfg1_base = pp->cfg.start + pp->config.cfg0_size;
+
+ pp->va_cfg0_base = devm_ioremap(pp->dev, pp->cfg0_base,
+ pp->config.cfg0_size);
+ if (!pp->va_cfg0_base) {
+ dev_err(pp->dev, "error with ioremap in function\n");
+ return -ENOMEM;
+ }
+ pp->va_cfg1_base = devm_ioremap(pp->dev, pp->cfg1_base,
+ pp->config.cfg1_size);
+ if (!pp->va_cfg1_base) {
+ dev_err(pp->dev, "error with ioremap\n");
+ return -ENOMEM;
+ }
+
+ ret = dw_pcie_msi_host_init(pp, pp->dev->of_node, &msi_domain_ops);
+ if (ret < 0)
+ return ret;
+
+ return dw_pcie_common_host_init(pp, &dw_pci);
+}
+
static void dw_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32 busdev)
{
/* Program viewport 0 : OUTBOUND : CFG0 */
Regards
Pratyush

--
1.7.9.5

--
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/