[PATCH v7 1/6] pci: Introduce pci_register_io_range() helper function.

Rob Herring
2014-06-27T16:15:53Z

On 06/27/2014 07:49 AM, Will Deacon wrote:
> On Fri, Jun 27, 2014 at 12:03:34PM +0100, Arnd Bergmann wrote:
>> On Thursday 26 June 2014 19:44:21 Rob Herring wrote:
>>> I don't agree arm32 is harder than microblaze. Yes, converting ALL of
>>> arm would be, but that is not necessary. With Liviu's latest branch
>>> the hacks I previously needed are gone (thanks!), and this is all I
>>> need to get Versatile PCI working (under QEMU):
>>
>> I meant converting all of arm32 would be harder, but I agree we don't
>> have to do it. It would be nice to convert all of the drivers/pci/host
>> drivers though, iow all multiplatform-enabled ones, and leaving the
>> current arm32 pci implementation for the platforms we don't want to
>> convert to multiplatform anyway (footbridge, iop, ixp4xx, ks8695 (?),
>> pxa, sa1100).
>
> I'm more than happy to convert the generic host controller we merged
> recently, but I'd probably want the core changes merged first so that I
> know I'm not wasting my time!

Something like this untested patch...

Another issue I found still present is pci_ioremap_io needs some work
to unify with the arm implementation. That's a matter of changing the
function from an offset to i/o resource. That should be a pretty
mechanical change.

Also, there is a potential for memory leak because there is no undo
for of_create_pci_host_bridge.

Rob

8<------------------------------------------------------------------
>From 301b402631b2867ced38d5533586da0bd888045c Mon Sep 17 00:00:00 2001
From: Rob Herring <robh@kernel.org>
Date: Fri, 27 Jun 2014 09:46:09 -0500
Subject: [PATCH] pci: generic-host: refactor to use common range parsing

Signed-off-by: Rob Herring <robh@kernel.org>
---
drivers/pci/host/pci-host-generic.c | 191 ++++++------------------------------
1 file changed, 29 insertions(+), 162 deletions(-)

diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index 44fe6aa..57fd1e1 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -32,16 +32,14 @@ struct gen_pci_cfg_bus_ops {

struct gen_pci_cfg_windows {
struct resource res;
- struct resource bus_range;
void __iomem **win;

const struct gen_pci_cfg_bus_ops *ops;
};

struct gen_pci {
- struct pci_host_bridge host;
+ struct pci_host_bridge *host;
struct gen_pci_cfg_windows cfg;
- struct list_head resources;
};

static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
@@ -50,7 +48,7 @@ static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
{
struct pci_sys_data *sys = bus->sysdata;
struct gen_pci *pci = sys->private_data;
- resource_size_t idx = bus->number - pci->cfg.bus_range.start;
+ resource_size_t idx = bus->number - bus->busn_res.start;

return pci->cfg.win[idx] + ((devfn << 8) | where);
}
@@ -66,7 +64,7 @@ static void __iomem *gen_pci_map_cfg_bus_ecam(struct pci_bus *bus,
{
struct pci_sys_data *sys = bus->sysdata;
struct gen_pci *pci = sys->private_data;
- resource_size_t idx = bus->number - pci->cfg.bus_range.start;
+ resource_size_t idx = bus->number - bus->busn_res.start;

return pci->cfg.win[idx] + ((devfn << 12) | where);
}
@@ -138,154 +136,32 @@ static const struct of_device_id gen_pci_of_match[] = {
};
MODULE_DEVICE_TABLE(of, gen_pci_of_match);

-static int gen_pci_calc_io_offset(struct device *dev,
- struct of_pci_range *range,
- struct resource *res,
- resource_size_t *offset)
-{
- static atomic_t wins = ATOMIC_INIT(0);
- int err, idx, max_win;
- unsigned int window;
-
- if (!PAGE_ALIGNED(range->cpu_addr))
- return -EINVAL;
-
- max_win = (IO_SPACE_LIMIT + 1) / SZ_64K;
- idx = atomic_inc_return(&wins);
- if (idx > max_win)
- return -ENOSPC;
-
- window = (idx - 1) * SZ_64K;
- err = pci_ioremap_io(window, range->cpu_addr);
- if (err)
- return err;
-
- of_pci_range_to_resource(range, dev->of_node, res);
- res->start = window;
- res->end = res->start + range->size - 1;
- *offset = window - range->pci_addr;
- return 0;
-}
-
-static int gen_pci_calc_mem_offset(struct device *dev,
- struct of_pci_range *range,
- struct resource *res,
- resource_size_t *offset)
-{
- of_pci_range_to_resource(range, dev->of_node, res);
- *offset = range->cpu_addr - range->pci_addr;
- return 0;
-}
-
-static void gen_pci_release_of_pci_ranges(struct gen_pci *pci)
-{
- struct pci_host_bridge_window *win;
-
- list_for_each_entry(win, &pci->resources, list)
- release_resource(win->res);
-
- pci_free_resource_list(&pci->resources);
-}
-
-static int gen_pci_parse_request_of_pci_ranges(struct gen_pci *pci)
-{
- struct of_pci_range range;
- struct of_pci_range_parser parser;
- int err, res_valid = 0;
- struct device *dev = pci->host.dev.parent;
- struct device_node *np = dev->of_node;
-
- if (of_pci_range_parser_init(&parser, np)) {
- dev_err(dev, "missing \"ranges\" property\n");
- return -EINVAL;
- }
-
- for_each_of_pci_range(&parser, &range) {
- struct resource *parent, *res;
- resource_size_t offset;
- u32 restype = range.flags & IORESOURCE_TYPE_BITS;
-
- res = devm_kmalloc(dev, sizeof(*res), GFP_KERNEL);
- if (!res) {
- err = -ENOMEM;
- goto out_release_res;
- }
-
- switch (restype) {
- case IORESOURCE_IO:
- parent = &ioport_resource;
- err = gen_pci_calc_io_offset(dev, &range, res, &offset);
- break;
- case IORESOURCE_MEM:
- parent = &iomem_resource;
- err = gen_pci_calc_mem_offset(dev, &range, res, &offset);
- res_valid |= !(res->flags & IORESOURCE_PREFETCH || err);
- break;
- default:
- err = -EINVAL;
- continue;
- }
-
- if (err) {
- dev_warn(dev,
- "error %d: failed to add resource [type 0x%x, %lld bytes]\n",
- err, restype, range.size);
- continue;
- }
-
- err = request_resource(parent, res);
- if (err)
- goto out_release_res;
-
- pci_add_resource_offset(&pci->resources, res, offset);
- }
-
- if (!res_valid) {
- dev_err(dev, "non-prefetchable memory resource required\n");
- err = -EINVAL;
- goto out_release_res;
- }
-
- return 0;
-
-out_release_res:
- gen_pci_release_of_pci_ranges(pci);
- return err;
-}
-
static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
{
int err;
u8 bus_max;
resource_size_t busn;
- struct resource *bus_range;
- struct device *dev = pci->host.dev.parent;
+ struct pci_bus *bus = pci->host->bus;
+ struct resource *bus_range = &bus->busn_res;
+ struct device *dev = pci->host->dev.parent;
struct device_node *np = dev->of_node;

- if (of_pci_parse_bus_range(np, &pci->cfg.bus_range))
- pci->cfg.bus_range = (struct resource) {
- .name = np->name,
- .start = 0,
- .end = 0xff,
- .flags = IORESOURCE_BUS,
- };
-
err = of_address_to_resource(np, 0, &pci->cfg.res);
if (err) {
dev_err(dev, "missing \"reg\" property\n");
return err;
}

- pci->cfg.win = devm_kcalloc(dev, resource_size(&pci->cfg.bus_range),
+ pci->cfg.win = devm_kcalloc(dev, resource_size(bus_range),
sizeof(*pci->cfg.win), GFP_KERNEL);
if (!pci->cfg.win)
return -ENOMEM;

/* Limit the bus-range to fit within reg */
- bus_max = pci->cfg.bus_range.start +
+ bus_max = bus_range->start +
(resource_size(&pci->cfg.res) >> pci->cfg.ops->bus_shift) - 1;
- pci->cfg.bus_range.end = min_t(resource_size_t, pci->cfg.bus_range.end,
- bus_max);
+ pci_bus_update_busn_res_end(bus, min_t(resource_size_t,
+ bus_range->end, bus_max));

/* Map our Configuration Space windows */
if (!devm_request_mem_region(dev, pci->cfg.res.start,
@@ -293,7 +169,6 @@ static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
"Configuration Space"))
return -ENOMEM;

- bus_range = &pci->cfg.bus_range;
for (busn = bus_range->start; busn <= bus_range->end; ++busn) {
u32 idx = busn - bus_range->start;
u32 sz = 1 << pci->cfg.ops->bus_shift;
@@ -305,34 +180,21 @@ static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
return -ENOMEM;
}

- /* Register bus resource */
- pci_add_resource(&pci->resources, bus_range);
return 0;
}

-static int gen_pci_setup(int nr, struct pci_sys_data *sys)
-{
- struct gen_pci *pci = sys->private_data;
- list_splice_init(&pci->resources, &sys->resources);
- return 1;
-}
+/* Unused, temporary to satisfy ARM arch code */
+static struct pci_sys_data sys;

static int gen_pci_probe(struct platform_device *pdev)
{
- int err;
+ int err, lastbus;
const char *type;
const struct of_device_id *of_id;
const int *prop;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
- struct hw_pci hw = {
- .nr_controllers = 1,
- .private_data = (void **)&pci,
- .setup = gen_pci_setup,
- .map_irq = of_irq_parse_and_map_pci,
- .ops = &gen_pci_ops,
- };

if (!pci)
return -ENOMEM;
@@ -353,23 +215,28 @@ static int gen_pci_probe(struct platform_device *pdev)

of_id = of_match_node(gen_pci_of_match, np);
pci->cfg.ops = of_id->data;
- pci->host.dev.parent = dev;
- INIT_LIST_HEAD(&pci->host.windows);
- INIT_LIST_HEAD(&pci->resources);

- /* Parse our PCI ranges and request their resources */
- err = gen_pci_parse_request_of_pci_ranges(pci);
- if (err)
- return err;
+ pci->host = of_create_pci_host_bridge(&pdev->dev, &gen_pci_ops, &sys);
+ if (PTR_ERR(pci->host))
+ return PTR_ERR(pci->host);

/* Parse and map our Configuration Space windows */
err = gen_pci_parse_map_cfg_windows(pci);
- if (err) {
- gen_pci_release_of_pci_ranges(pci);
+ if (err)
return err;
- }

- pci_common_init_dev(dev, &hw);
+ pci_ioremap_io(0, pci->host->io_base);
+
+ pci_add_flags(PCI_ENABLE_PROC_DOMAINS);
+ pci_add_flags(PCI_REASSIGN_ALL_BUS | PCI_REASSIGN_ALL_RSRC);
+
+ lastbus = pci_scan_child_bus(pci->host->bus);
+ pci_bus_update_busn_res_end(pci->host->bus, lastbus);
+
+ pci_assign_unassigned_bus_resources(pci->host->bus);
+
+ pci_bus_add_devices(pci->host->bus);
+
return 0;
}

--
1.9.1