Reuse the debugging features which were available in pxa architecture. This is a copy of the code from arch/arm/plat-pxa/dma, which is doomed to disappear once the conversion is completed towards dmaengine. This is a transfer of the commit "[ARM] pxa/dma: add debugfs entries" (d294948c2ce4e1c85f452154469752cc9b8e876d). Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx> --- Since v2: bissectability --- drivers/dma/pxa_dma.c | 242 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 242 insertions(+) diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c index bad1b36..f0912a2 100644 --- a/drivers/dma/pxa_dma.c +++ b/drivers/dma/pxa_dma.c @@ -131,6 +131,11 @@ struct pxad_device { void __iomem *base; struct pxad_phy *phys; spinlock_t phy_lock; /* Phy association */ +#ifdef CONFIG_DEBUG_FS + struct dentry *dbgfs_root; + struct dentry *dbgfs_state; + struct dentry **dbgfs_chan; +#endif }; #define tx_to_pxad_desc(tx) \ @@ -168,6 +173,241 @@ struct pxad_device { __func__, (u32)(val), #_reg); \ } while (0) +/* + * Debug fs + */ +#ifdef CONFIG_DEBUG_FS +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/seq_file.h> + +static int dbg_show_requester_chan(struct seq_file *s, void *p) +{ + int pos = 0; + struct pxad_phy *phy = s->private; + int i; + u32 drcmr; + + pos += seq_printf(s, "DMA channel %d requester :\n", phy->idx); + for (i = 0; i < 70; i++) { + drcmr = readl_relaxed(phy->base + DRCMR(i)); + if ((drcmr & DRCMR_CHLNUM) == phy->idx) + pos += seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i, + !!(drcmr & DRCMR_MAPVLD)); + } + return pos; +} + +static inline int dbg_burst_from_dcmd(u32 dcmd) +{ + int burst = (dcmd >> 16) & 0x3; + + return burst ? 4 << burst : 0; +} + +static int is_phys_valid(unsigned long addr) +{ + return pfn_valid(__phys_to_pfn(addr)); +} + +#define DCSR_STR(flag) (dcsr & DCSR_##flag ? #flag" " : "") +#define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "") + +static int dbg_show_descriptors(struct seq_file *s, void *p) +{ + struct pxad_phy *phy = s->private; + int i, max_show = 20, burst, width; + u32 dcmd; + unsigned long phys_desc, ddadr; + struct pxad_desc_hw *desc; + + phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR); + + seq_printf(s, "DMA channel %d descriptors :\n", phy->idx); + seq_printf(s, "[%03d] First descriptor unknown\n", 0); + for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) { + desc = phys_to_virt(phys_desc); + dcmd = desc->dcmd; + burst = dbg_burst_from_dcmd(dcmd); + width = (1 << ((dcmd >> 14) & 0x3)) >> 1; + + seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n", + i, phys_desc, desc); + seq_printf(s, "\tDDADR = %08x\n", desc->ddadr); + seq_printf(s, "\tDSADR = %08x\n", desc->dsadr); + seq_printf(s, "\tDTADR = %08x\n", desc->dtadr); + seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n", + dcmd, + PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR), + PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG), + PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN), + PXA_DCMD_STR(ENDIAN), burst, width, + dcmd & PXA_DCMD_LENGTH); + phys_desc = desc->ddadr; + } + if (i == max_show) + seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n", + i, phys_desc); + else + seq_printf(s, "[%03d] Desc at %08lx is %s\n", + i, phys_desc, phys_desc == DDADR_STOP ? + "DDADR_STOP" : "invalid"); + + return 0; +} + +static int dbg_show_chan_state(struct seq_file *s, void *p) +{ + struct pxad_phy *phy = s->private; + u32 dcsr, dcmd; + int burst, width; + static const char * const str_prio[] = { + "high", "normal", "low", "invalid" + }; + + dcsr = _phy_readl_relaxed(phy, DCSR); + dcmd = _phy_readl_relaxed(phy, DCMD); + burst = dbg_burst_from_dcmd(dcmd); + width = (1 << ((dcmd >> 14) & 0x3)) >> 1; + + seq_printf(s, "DMA channel %d\n", phy->idx); + seq_printf(s, "\tPriority : %s\n", + str_prio[(phy->idx & 0xf) / 4]); + seq_printf(s, "\tUnaligned transfer bit: %s\n", + _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ? + "yes" : "no"); + seq_printf(s, "\tDCSR = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n", + dcsr, DCSR_STR(RUN), DCSR_STR(NODESC), + DCSR_STR(STOPIRQEN), DCSR_STR(EORIRQEN), + DCSR_STR(EORJMPEN), DCSR_STR(EORSTOPEN), + DCSR_STR(SETCMPST), DCSR_STR(CLRCMPST), + DCSR_STR(CMPST), DCSR_STR(EORINTR), DCSR_STR(REQPEND), + DCSR_STR(STOPSTATE), DCSR_STR(ENDINTR), + DCSR_STR(STARTINTR), DCSR_STR(BUSERR)); + + seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n", + dcmd, + PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR), + PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG), + PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN), + PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH); + seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR)); + seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR)); + seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR)); + + return 0; +} + +static int dbg_show_state(struct seq_file *s, void *p) +{ + struct pxad_device *pdev = s->private; + + /* basic device status */ + seq_puts(s, "DMA engine status\n"); + seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans); + + return 0; +} + +#define DBGFS_FUNC_DECL(name) \ +static int dbg_open_##name(struct inode *inode, struct file *file) \ +{ \ + return single_open(file, dbg_show_##name, inode->i_private); \ +} \ +static const struct file_operations dbg_fops_##name = { \ + .owner = THIS_MODULE, \ + .open = dbg_open_##name, \ + .llseek = seq_lseek, \ + .read = seq_read, \ + .release = single_release, \ +} + +DBGFS_FUNC_DECL(state); +DBGFS_FUNC_DECL(chan_state); +DBGFS_FUNC_DECL(descriptors); +DBGFS_FUNC_DECL(requester_chan); + +static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev, + int ch, struct dentry *chandir) +{ + char chan_name[11]; + struct dentry *chan, *chan_state = NULL, *chan_descr = NULL; + struct dentry *chan_reqs = NULL; + void *dt; + + scnprintf(chan_name, sizeof(chan_name), "%d", ch); + chan = debugfs_create_dir(chan_name, chandir); + dt = (void *)&pdev->phys[ch]; + + if (chan) + chan_state = debugfs_create_file("state", 0400, chan, dt, + &dbg_fops_chan_state); + if (chan_state) + chan_descr = debugfs_create_file("descriptors", 0400, chan, dt, + &dbg_fops_descriptors); + if (chan_descr) + chan_reqs = debugfs_create_file("requesters", 0400, chan, dt, + &dbg_fops_requester_chan); + if (!chan_reqs) + goto err_state; + + return chan; + +err_state: + debugfs_remove_recursive(chan); + return NULL; +} + +static void pxad_init_debugfs(struct pxad_device *pdev) +{ + int i; + struct dentry *chandir; + + pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL); + if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root) + goto err_root; + + pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root, + pdev, &dbg_fops_state); + if (!pdev->dbgfs_state) + goto err_state; + + pdev->dbgfs_chan = + kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state), + GFP_KERNEL); + if (!pdev->dbgfs_chan) + goto err_alloc; + + chandir = debugfs_create_dir("channels", pdev->dbgfs_root); + if (!chandir) + goto err_chandir; + + for (i = 0; i < pdev->nr_chans; i++) { + pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir); + if (!pdev->dbgfs_chan[i]) + goto err_chans; + } + + return; +err_chans: +err_chandir: + kfree(pdev->dbgfs_chan); +err_alloc: +err_state: + debugfs_remove_recursive(pdev->dbgfs_root); +err_root: + pr_err("pxad: debugfs is not available\n"); +} + +static void pxad_cleanup_debugfs(struct pxad_device *pdev) +{ + debugfs_remove_recursive(pdev->dbgfs_root); +} +#else +static inline void pxad_init_debugfs(struct pxad_device *pdev) {} +static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {} +#endif + static struct pxad_phy *lookup_phy(struct pxad_chan *pchan) { int prio, i; @@ -981,6 +1221,7 @@ static int pxad_remove(struct platform_device *op) { struct pxad_device *pdev = platform_get_drvdata(op); + pxad_cleanup_debugfs(pdev); pxad_free_channels(&pdev->slave); dma_async_device_unregister(&pdev->slave); return 0; @@ -1153,6 +1394,7 @@ static int pxad_probe(struct platform_device *op) } platform_set_drvdata(op, pdev); + pxad_init_debugfs(pdev); dev_info(pdev->slave.dev, "initialized %d channels\n", dma_channels); return 0; } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html