From 541b9bad169d2422c7c7e3905b105930a1b6eb32 Mon Sep 17 00:00:00 2001 From: "Maciej S. Szmigiero" Date: Wed, 14 Feb 2018 00:06:18 +0100 Subject: [PATCH] ALSA: emu10k1: add optional debug printouts with DMA addresses When we get a IOMMU page fault for a emu10k1 device it is very hard to discover which of chip many DMA allocations triggered it (since on a IOMMU system the DMA address space is often very different from the CPU one). Let's add optional debug printouts providing this information. These debug printouts are only enabled on an explicit request via the kernel dynamic debug mechanism. Signed-off-by: Maciej S. Szmigiero Signed-off-by: Takashi Iwai --- sound/pci/emu10k1/emu10k1_main.c | 8 ++++++++ sound/pci/emu10k1/memory.c | 15 +++++++++++---- 2 files changed, 19 insertions(+), 4 deletions(-) diff --git a/sound/pci/emu10k1/emu10k1_main.c b/sound/pci/emu10k1/emu10k1_main.c index 11e868f569d6..8decd2a7a404 100644 --- a/sound/pci/emu10k1/emu10k1_main.c +++ b/sound/pci/emu10k1/emu10k1_main.c @@ -1898,6 +1898,9 @@ int snd_emu10k1_create(struct snd_card *card, err = -ENOMEM; goto error; } + dev_dbg(card->dev, "page table address range is %.8lx:%.8lx\n", + (unsigned long)emu->ptb_pages.addr, + (unsigned long)(emu->ptb_pages.addr + emu->ptb_pages.bytes)); emu->page_ptr_table = vmalloc(emu->max_cache_pages * sizeof(void *)); emu->page_addr_table = vmalloc(emu->max_cache_pages * @@ -1912,6 +1915,11 @@ int snd_emu10k1_create(struct snd_card *card, err = -ENOMEM; goto error; } + dev_dbg(card->dev, "silent page range is %.8lx:%.8lx\n", + (unsigned long)emu->silent_page.addr, + (unsigned long)(emu->silent_page.addr + + emu->silent_page.bytes)); + emu->memhdr = snd_util_memhdr_new(emu->max_cache_pages * PAGE_SIZE); if (emu->memhdr == NULL) { err = -ENOMEM; diff --git a/sound/pci/emu10k1/memory.c b/sound/pci/emu10k1/memory.c index eaa61024ac7f..fcb04cbbc9ab 100644 --- a/sound/pci/emu10k1/memory.c +++ b/sound/pci/emu10k1/memory.c @@ -34,7 +34,10 @@ * aligned pages in others */ #define __set_ptb_entry(emu,page,addr) \ - (((u32 *)(emu)->ptb_pages.area)[page] = cpu_to_le32(((addr) << (emu->address_mode)) | (page))) + (((__le32 *)(emu)->ptb_pages.area)[page] = \ + cpu_to_le32(((addr) << (emu->address_mode)) | (page))) +#define __get_ptb_entry(emu, page) \ + (le32_to_cpu(((__le32 *)(emu)->ptb_pages.area)[page])) #define UNIT_PAGES (PAGE_SIZE / EMUPAGESIZE) #define MAX_ALIGN_PAGES0 (MAXPAGES0 / UNIT_PAGES) @@ -44,8 +47,7 @@ /* get offset address from aligned page */ #define aligned_page_offset(page) ((page) << PAGE_SHIFT) -#if PAGE_SIZE == 4096 -/* page size == EMUPAGESIZE */ +#if PAGE_SIZE == EMUPAGESIZE && !IS_ENABLED(CONFIG_DYNAMIC_DEBUG) /* fill PTB entrie(s) corresponding to page with addr */ #define set_ptb_entry(emu,page,addr) __set_ptb_entry(emu,page,addr) /* fill PTB entrie(s) corresponding to page with silence pointer */ @@ -58,6 +60,8 @@ static inline void set_ptb_entry(struct snd_emu10k1 *emu, int page, dma_addr_t a page *= UNIT_PAGES; for (i = 0; i < UNIT_PAGES; i++, page++) { __set_ptb_entry(emu, page, addr); + dev_dbg(emu->card->dev, "mapped page %d to entry %.8x\n", page, + (unsigned int)__get_ptb_entry(emu, page)); addr += EMUPAGESIZE; } } @@ -65,9 +69,12 @@ static inline void set_silent_ptb(struct snd_emu10k1 *emu, int page) { int i; page *= UNIT_PAGES; - for (i = 0; i < UNIT_PAGES; i++, page++) + for (i = 0; i < UNIT_PAGES; i++, page++) { /* do not increment ptr */ __set_ptb_entry(emu, page, emu->silent_page.addr); + dev_dbg(emu->card->dev, "mapped silent page %d to entry %.8x\n", + page, (unsigned int)__get_ptb_entry(emu, page)); + } } #endif /* PAGE_SIZE */