From 72cac213fda6a2dd402e91692b70e175795eab7d Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 23 May 2008 14:21:30 +1000 Subject: [PATCH] [POWERPC] Add debugging trigger to Axon MSI code This adds some debugging code to the Axon MSI driver. It creates a file per MSIC in /sys/kernel/debug/powerpc, which allows the user to trigger a fake MSI interrupt by writing to the file. This can be used to test some of the MSI generation path. In particular, that the MSIC recognises a write to the MSI address, generates an interrupt and writes the MSI packet into the ring buffer. All the code is inside #ifdef DEBUG so it causes no harm unless it's enabled. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/cell/axon_msi.c | 58 ++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) diff --git a/arch/powerpc/platforms/cell/axon_msi.c b/arch/powerpc/platforms/cell/axon_msi.c index c39f5c225f2e..8b055bce27fe 100644 --- a/arch/powerpc/platforms/cell/axon_msi.c +++ b/arch/powerpc/platforms/cell/axon_msi.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -69,8 +70,19 @@ struct axon_msic { dma_addr_t fifo_phys; dcr_host_t dcr_host; u32 read_offset; +#ifdef DEBUG + u32 __iomem *trigger; +#endif }; +#ifdef DEBUG +void axon_msi_debug_setup(struct device_node *dn, struct axon_msic *msic); +#else +static inline void axon_msi_debug_setup(struct device_node *dn, + struct axon_msic *msic) { } +#endif + + static void msic_dcr_write(struct axon_msic *msic, unsigned int dcr_n, u32 val) { pr_debug("axon_msi: dcr_write(0x%x, 0x%x)\n", val, dcr_n); @@ -381,6 +393,8 @@ static int axon_msi_probe(struct of_device *device, ppc_md.teardown_msi_irqs = axon_msi_teardown_msi_irqs; ppc_md.msi_check_device = axon_msi_check_device; + axon_msi_debug_setup(dn, msic); + printk(KERN_DEBUG "axon_msi: setup MSIC on %s\n", dn->full_name); return 0; @@ -418,3 +432,47 @@ static int __init axon_msi_init(void) return of_register_platform_driver(&axon_msi_driver); } subsys_initcall(axon_msi_init); + + +#ifdef DEBUG +static int msic_set(void *data, u64 val) +{ + struct axon_msic *msic = data; + out_le32(msic->trigger, val); + return 0; +} + +static int msic_get(void *data, u64 *val) +{ + *val = 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_msic, msic_get, msic_set, "%llu\n"); + +void axon_msi_debug_setup(struct device_node *dn, struct axon_msic *msic) +{ + char name[8]; + u64 addr; + + addr = of_translate_address(dn, of_get_property(dn, "reg", NULL)); + if (addr == OF_BAD_ADDR) { + pr_debug("axon_msi: couldn't translate reg property\n"); + return; + } + + msic->trigger = ioremap(addr, 0x4); + if (!msic->trigger) { + pr_debug("axon_msi: ioremap failed\n"); + return; + } + + snprintf(name, sizeof(name), "msic_%d", of_node_to_nid(dn)); + + if (!debugfs_create_file(name, 0600, powerpc_debugfs_root, + msic, &fops_msic)) { + pr_debug("axon_msi: debugfs_create_file failed!\n"); + return; + } +} +#endif /* DEBUG */ -- 2.39.5