// SPDX-License-Identifier: GPL-2.0 /* * Copyright(C) 2016 Linaro Limited. All rights reserved. * Author: Mathieu Poirier */ #include #include #include #include #include #include #include #include #include #include #include "coresight-catu.h" #include "coresight-etm-perf.h" #include "coresight-priv.h" #include "coresight-tmc.h" struct etr_flat_buf { struct device *dev; dma_addr_t daddr; void *vaddr; size_t size; }; /* * etr_perf_buffer - Perf buffer used for ETR * @drvdata - The ETR drvdaga this buffer has been allocated for. * @etr_buf - Actual buffer used by the ETR * @pid - The PID this etr_perf_buffer belongs to. * @snaphost - Perf session mode * @nr_pages - Number of pages in the ring buffer. * @pages - Array of Pages in the ring buffer. */ struct etr_perf_buffer { struct tmc_drvdata *drvdata; struct etr_buf *etr_buf; pid_t pid; bool snapshot; int nr_pages; void **pages; }; /* Convert the perf index to an offset within the ETR buffer */ #define PERF_IDX2OFF(idx, buf) \ ((idx) % ((unsigned long)(buf)->nr_pages << PAGE_SHIFT)) /* Lower limit for ETR hardware buffer */ #define TMC_ETR_PERF_MIN_BUF_SIZE SZ_1M /* * The TMC ETR SG has a page size of 4K. The SG table contains pointers * to 4KB buffers. However, the OS may use a PAGE_SIZE different from * 4K (i.e, 16KB or 64KB). This implies that a single OS page could * contain more than one SG buffer and tables. * * A table entry has the following format: * * ---Bit31------------Bit4-------Bit1-----Bit0-- * | Address[39:12] | SBZ | Entry Type | * ---------------------------------------------- * * Address: Bits [39:12] of a physical page address. Bits [11:0] are * always zero. * * Entry type: * b00 - Reserved. * b01 - Last entry in the tables, points to 4K page buffer. * b10 - Normal entry, points to 4K page buffer. * b11 - Link. The address points to the base of next table. */ typedef u32 sgte_t; #define ETR_SG_PAGE_SHIFT 12 #define ETR_SG_PAGE_SIZE (1UL << ETR_SG_PAGE_SHIFT) #define ETR_SG_PAGES_PER_SYSPAGE (PAGE_SIZE / ETR_SG_PAGE_SIZE) #define ETR_SG_PTRS_PER_PAGE (ETR_SG_PAGE_SIZE / sizeof(sgte_t)) #define ETR_SG_PTRS_PER_SYSPAGE (PAGE_SIZE / sizeof(sgte_t)) #define ETR_SG_ET_MASK 0x3 #define ETR_SG_ET_LAST 0x1 #define ETR_SG_ET_NORMAL 0x2 #define ETR_SG_ET_LINK 0x3 #define ETR_SG_ADDR_SHIFT 4 #define ETR_SG_ENTRY(addr, type) \ (sgte_t)((((addr) >> ETR_SG_PAGE_SHIFT) << ETR_SG_ADDR_SHIFT) | \ (type & ETR_SG_ET_MASK)) #define ETR_SG_ADDR(entry) \ (((dma_addr_t)(entry) >> ETR_SG_ADDR_SHIFT) << ETR_SG_PAGE_SHIFT) #define ETR_SG_ET(entry) ((entry) & ETR_SG_ET_MASK) /* * struct etr_sg_table : ETR SG Table * @sg_table: Generic SG Table holding the data/table pages. * @hwaddr: hwaddress used by the TMC, which is the base * address of the table. */ struct etr_sg_table { struct tmc_sg_table *sg_table; dma_addr_t hwaddr; }; /* * tmc_etr_sg_table_entries: Total number of table entries required to map * @nr_pages system pages. * * We need to map @nr_pages * ETR_SG_PAGES_PER_SYSPAGE data pages. * Each TMC page can map (ETR_SG_PTRS_PER_PAGE - 1) buffer pointers, * with the last entry pointing to another page of table entries. * If we spill over to a new page for mapping 1 entry, we could as * well replace the link entry of the previous page with the last entry. */ static inline unsigned long __attribute_const__ tmc_etr_sg_table_entries(int nr_pages) { unsigned long nr_sgpages = nr_pages * ETR_SG_PAGES_PER_SYSPAGE; unsigned long nr_sglinks = nr_sgpages / (ETR_SG_PTRS_PER_PAGE - 1); /* * If we spill over to a new page for 1 entry, we could as well * make it the LAST entry in the previous page, skipping the Link * address. */ if (nr_sglinks && (nr_sgpages % (ETR_SG_PTRS_PER_PAGE - 1) < 2)) nr_sglinks--; return nr_sgpages + nr_sglinks; } /* * tmc_pages_get_offset: Go through all the pages in the tmc_pages * and map the device address @addr to an offset within the virtual * contiguous buffer. */ static long tmc_pages_get_offset(struct tmc_pages *tmc_pages, dma_addr_t addr) { int i; dma_addr_t page_start; for (i = 0; i < tmc_pages->nr_pages; i++) { page_start = tmc_pages->daddrs[i]; if (addr >= page_start && addr < (page_start + PAGE_SIZE)) return i * PAGE_SIZE + (addr - page_start); } return -EINVAL; } /* * tmc_pages_free : Unmap and free the pages used by tmc_pages. * If the pages were not allocated in tmc_pages_alloc(), we would * simply drop the refcount. */ static void tmc_pages_free(struct tmc_pages *tmc_pages, struct device *dev, enum dma_data_direction dir) { int i; struct device *real_dev = dev->parent; for (i = 0; i < tmc_pages->nr_pages; i++) { if (tmc_pages->daddrs && tmc_pages->daddrs[i]) dma_unmap_page(real_dev, tmc_pages->daddrs[i], PAGE_SIZE, dir); if (tmc_pages->pages && tmc_pages->pages[i]) __free_page(tmc_pages->pages[i]); } kfree(tmc_pages->pages); kfree(tmc_pages->daddrs); tmc_pages->pages = NULL; tmc_pages->daddrs = NULL; tmc_pages->nr_pages = 0; } /* * tmc_pages_alloc : Allocate and map pages for a given @tmc_pages. * If @pages is not NULL, the list of page virtual addresses are * used as the data pages. The pages are then dma_map'ed for @dev * with dma_direction @dir. * * Returns 0 upon success, else the error number. */ static int tmc_pages_alloc(struct tmc_pages *tmc_pages, struct device *dev, int node, enum dma_data_direction dir, void **pages) { int i, nr_pages; dma_addr_t paddr; struct page *page; struct device *real_dev = dev->parent; nr_pages = tmc_pages->nr_pages; tmc_pages->daddrs = kcalloc(nr_pages, sizeof(*tmc_pages->daddrs), GFP_KERNEL); if (!tmc_pages->daddrs) return -ENOMEM; tmc_pages->pages = kcalloc(nr_pages, sizeof(*tmc_pages->pages), GFP_KERNEL); if (!tmc_pages->pages) { kfree(tmc_pages->daddrs); tmc_pages->daddrs = NULL; return -ENOMEM; } for (i = 0; i < nr_pages; i++) { if (pages && pages[i]) { page = virt_to_page(pages[i]); /* Hold a refcount on the page */ get_page(page); } else { page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0); if (!page) goto err; } paddr = dma_map_page(real_dev, page, 0, PAGE_SIZE, dir); if (dma_mapping_error(real_dev, paddr)) goto err; tmc_pages->daddrs[i] = paddr; tmc_pages->pages[i] = page; } return 0; err: tmc_pages_free(tmc_pages, dev, dir); return -ENOMEM; } static inline long tmc_sg_get_data_page_offset(struct tmc_sg_table *sg_table, dma_addr_t addr) { return tmc_pages_get_offset(&sg_table->data_pages, addr); } static inline void tmc_free_table_pages(struct tmc_sg_table *sg_table) { if (sg_table->table_vaddr) vunmap(sg_table->table_vaddr); tmc_pages_free(&sg_table->table_pages, sg_table->dev, DMA_TO_DEVICE); } static void tmc_free_data_pages(struct tmc_sg_table *sg_table) { if (sg_table->data_vaddr) vunmap(sg_table->data_vaddr); tmc_pages_free(&sg_table->data_pages, sg_table->dev, DMA_FROM_DEVICE); } void tmc_free_sg_table(struct tmc_sg_table *sg_table) { tmc_free_table_pages(sg_table); tmc_free_data_pages(sg_table); } EXPORT_SYMBOL_GPL(tmc_free_sg_table); /* * Alloc pages for the table. Since this will be used by the device, * allocate the pages closer to the device (i.e, dev_to_node(dev) * rather than the CPU node). */ static int tmc_alloc_table_pages(struct tmc_sg_table *sg_table) { int rc; struct tmc_pages *table_pages = &sg_table->table_pages; rc = tmc_pages_alloc(table_pages, sg_table->dev, dev_to_node(sg_table->dev), DMA_TO_DEVICE, NULL); if (rc) return rc; sg_table->table_vaddr = vmap(table_pages->pages, table_pages->nr_pages, VM_MAP, PAGE_KERNEL); if (!sg_table->table_vaddr) rc = -ENOMEM; else sg_table->table_daddr = table_pages->daddrs[0]; return rc; } static int tmc_alloc_data_pages(struct tmc_sg_table *sg_table, void **pages) { int rc; /* Allocate data pages on the node requested by the caller */ rc = tmc_pages_alloc(&sg_table->data_pages, sg_table->dev, sg_table->node, DMA_FROM_DEVICE, pages); if (!rc) { sg_table->data_vaddr = vmap(sg_table->data_pages.pages, sg_table->data_pages.nr_pages, VM_MAP, PAGE_KERNEL); if (!sg_table->data_vaddr) rc = -ENOMEM; } return rc; } /* * tmc_alloc_sg_table: Allocate and setup dma pages for the TMC SG table * and data buffers. TMC writes to the data buffers and reads from the SG * Table pages. * * @dev - Coresight device to which page should be DMA mapped. * @node - Numa node for mem allocations * @nr_tpages - Number of pages for the table entries. * @nr_dpages - Number of pages for Data buffer. * @pages - Optional list of virtual address of pages. */ struct tmc_sg_table *tmc_alloc_sg_table(struct device *dev, int node, int nr_tpages, int nr_dpages, void **pages) { long rc; struct tmc_sg_table *sg_table; sg_table = kzalloc(sizeof(*sg_table), GFP_KERNEL); if (!sg_table) return ERR_PTR(-ENOMEM); sg_table->data_pages.nr_pages = nr_dpages; sg_table->table_pages.nr_pages = nr_tpages; sg_table->node = node; sg_table->dev = dev; rc = tmc_alloc_data_pages(sg_table, pages); if (!rc) rc = tmc_alloc_table_pages(sg_table); if (rc) { tmc_free_sg_table(sg_table); kfree(sg_table); return ERR_PTR(rc); } return sg_table; } EXPORT_SYMBOL_GPL(tmc_alloc_sg_table); /* * tmc_sg_table_sync_data_range: Sync the data buffer written * by the device from @offset upto a @size bytes. */ void tmc_sg_table_sync_data_range(struct tmc_sg_table *table, u64 offset, u64 size) { int i, index, start; int npages = DIV_ROUND_UP(size, PAGE_SIZE); struct device *real_dev = table->dev->parent; struct tmc_pages *data = &table->data_pages; start = offset >> PAGE_SHIFT; for (i = start; i < (start + npages); i++) { index = i % data->nr_pages; dma_sync_single_for_cpu(real_dev, data->daddrs[index], PAGE_SIZE, DMA_FROM_DEVICE); } } EXPORT_SYMBOL_GPL(tmc_sg_table_sync_data_range); /* tmc_sg_sync_table: Sync the page table */ void tmc_sg_table_sync_table(struct tmc_sg_table *sg_table) { int i; struct device *real_dev = sg_table->dev->parent; struct tmc_pages *table_pages = &sg_table->table_pages; for (i = 0; i < table_pages->nr_pages; i++) dma_sync_single_for_device(real_dev, table_pages->daddrs[i], PAGE_SIZE, DMA_TO_DEVICE); } EXPORT_SYMBOL_GPL(tmc_sg_table_sync_table); /* * tmc_sg_table_get_data: Get the buffer pointer for data @offset * in the SG buffer. The @bufpp is updated to point to the buffer. * Returns : * the length of linear data available at @offset. * or * <= 0 if no data is available. */ ssize_t tmc_sg_table_get_data(struct tmc_sg_table *sg_table, u64 offset, size_t len, char **bufpp) { size_t size; int pg_idx = offset >> PAGE_SHIFT; int pg_offset = offset & (PAGE_SIZE - 1); struct tmc_pages *data_pages = &sg_table->data_pages; size = tmc_sg_table_buf_size(sg_table); if (offset >= size) return -EINVAL; /* Make sure we don't go beyond the end */ len = (len < (size - offset)) ? len : size - offset; /* Respect the page boundaries */ len = (len < (PAGE_SIZE - pg_offset)) ? len : (PAGE_SIZE - pg_offset); if (len > 0) *bufpp = page_address(data_pages->pages[pg_idx]) + pg_offset; return len; } EXPORT_SYMBOL_GPL(tmc_sg_table_get_data); #ifdef ETR_SG_DEBUG /* Map a dma address to virtual address */ static unsigned long tmc_sg_daddr_to_vaddr(struct tmc_sg_table *sg_table, dma_addr_t addr, bool table) { long offset; unsigned long base; struct tmc_pages *tmc_pages; if (table) { tmc_pages = &sg_table->table_pages; base = (unsigned long)sg_table->table_vaddr; } else { tmc_pages = &sg_table->data_pages; base = (unsigned long)sg_table->data_vaddr; } offset = tmc_pages_get_offset(tmc_pages, addr); if (offset < 0) return 0; return base + offset; } /* Dump the given sg_table */ static void tmc_etr_sg_table_dump(struct etr_sg_table *etr_table) { sgte_t *ptr; int i = 0; dma_addr_t addr; struct tmc_sg_table *sg_table = etr_table->sg_table; ptr = (sgte_t *)tmc_sg_daddr_to_vaddr(sg_table, etr_table->hwaddr, true); while (ptr) { addr = ETR_SG_ADDR(*ptr); switch (ETR_SG_ET(*ptr)) { case ETR_SG_ET_NORMAL: dev_dbg(sg_table->dev, "%05d: %p\t:[N] 0x%llx\n", i, ptr, addr); ptr++; break; case ETR_SG_ET_LINK: dev_dbg(sg_table->dev, "%05d: *** %p\t:{L} 0x%llx ***\n", i, ptr, addr); ptr = (sgte_t *)tmc_sg_daddr_to_vaddr(sg_table, addr, true); break; case ETR_SG_ET_LAST: dev_dbg(sg_table->dev, "%05d: ### %p\t:[L] 0x%llx ###\n", i, ptr, addr); return; default: dev_dbg(sg_table->dev, "%05d: xxx %p\t:[INVALID] 0x%llx xxx\n", i, ptr, addr); return; } i++; } dev_dbg(sg_table->dev, "******* End of Table *****\n"); } #else static inline void tmc_etr_sg_table_dump(struct etr_sg_table *etr_table) {} #endif /* * Populate the SG Table page table entries from table/data * pages allocated. Each Data page has ETR_SG_PAGES_PER_SYSPAGE SG pages. * So does a Table page. So we keep track of indices of the tables * in each system page and move the pointers accordingly. */ #define INC_IDX_ROUND(idx, size) ((idx) = ((idx) + 1) % (size)) static void tmc_etr_sg_table_populate(struct etr_sg_table *etr_table) { dma_addr_t paddr; int i, type, nr_entries; int tpidx = 0; /* index to the current system table_page */ int sgtidx = 0; /* index to the sg_table within the current syspage */ int sgtentry = 0; /* the entry within the sg_table */ int dpidx = 0; /* index to the current system data_page */ int spidx = 0; /* index to the SG page within the current data page */ sgte_t *ptr; /* pointer to the table entry to fill */ struct tmc_sg_table *sg_table = etr_table->sg_table; dma_addr_t *table_daddrs = sg_table->table_pages.daddrs; dma_addr_t *data_daddrs = sg_table->data_pages.daddrs; nr_entries = tmc_etr_sg_table_entries(sg_table->data_pages.nr_pages); /* * Use the contiguous virtual address of the table to update entries. */ ptr = sg_table->table_vaddr; /* * Fill all the entries, except the last entry to avoid special * checks within the loop. */ for (i = 0; i < nr_entries - 1; i++) { if (sgtentry == ETR_SG_PTRS_PER_PAGE - 1) { /* * Last entry in a sg_table page is a link address to * the next table page. If this sg_table is the last * one in the system page, it links to the first * sg_table in the next system page. Otherwise, it * links to the next sg_table page within the system * page. */ if (sgtidx == ETR_SG_PAGES_PER_SYSPAGE - 1) { paddr = table_daddrs[tpidx + 1]; } else { paddr = table_daddrs[tpidx] + (ETR_SG_PAGE_SIZE * (sgtidx + 1)); } type = ETR_SG_ET_LINK; } else { /* * Update the indices to the data_pages to point to the * next sg_page in the data buffer. */ type = ETR_SG_ET_NORMAL; paddr = data_daddrs[dpidx] + spidx * ETR_SG_PAGE_SIZE; if (!INC_IDX_ROUND(spidx, ETR_SG_PAGES_PER_SYSPAGE)) dpidx++; } *ptr++ = ETR_SG_ENTRY(paddr, type); /* * Move to the next table pointer, moving the table page index * if necessary */ if (!INC_IDX_ROUND(sgtentry, ETR_SG_PTRS_PER_PAGE)) { if (!INC_IDX_ROUND(sgtidx, ETR_SG_PAGES_PER_SYSPAGE)) tpidx++; } } /* Set up the last entry, which is always a data pointer */ paddr = data_daddrs[dpidx] + spidx * ETR_SG_PAGE_SIZE; *ptr++ = ETR_SG_ENTRY(paddr, ETR_SG_ET_LAST); } /* * tmc_init_etr_sg_table: Allocate a TMC ETR SG table, data buffer of @size and * populate the table. * * @dev - Device pointer for the TMC * @node - NUMA node where the memory should be allocated * @size - Total size of the data buffer * @pages - Optional list of page virtual address */ static struct etr_sg_table * tmc_init_etr_sg_table(struct device *dev, int node, unsigned long size, void **pages) { int nr_entries, nr_tpages; int nr_dpages = size >> PAGE_SHIFT; struct tmc_sg_table *sg_table; struct etr_sg_table *etr_table; etr_table = kzalloc(sizeof(*etr_table), GFP_KERNEL); if (!etr_table) return ERR_PTR(-ENOMEM); nr_entries = tmc_etr_sg_table_entries(nr_dpages); nr_tpages = DIV_ROUND_UP(nr_entries, ETR_SG_PTRS_PER_SYSPAGE); sg_table = tmc_alloc_sg_table(dev, node, nr_tpages, nr_dpages, pages); if (IS_ERR(sg_table)) { kfree(etr_table); return ERR_CAST(sg_table); } etr_table->sg_table = sg_table; /* TMC should use table base address for DBA */ etr_table->hwaddr = sg_table->table_daddr; tmc_etr_sg_table_populate(etr_table); /* Sync the table pages for the HW */ tmc_sg_table_sync_table(sg_table); tmc_etr_sg_table_dump(etr_table); return etr_table; } /* * tmc_etr_alloc_flat_buf: Allocate a contiguous DMA buffer. */ static int tmc_etr_alloc_flat_buf(struct tmc_drvdata *drvdata, struct etr_buf *etr_buf, int node, void **pages) { struct etr_flat_buf *flat_buf; struct device *real_dev = drvdata->csdev->dev.parent; /* We cannot reuse existing pages for flat buf */ if (pages) return -EINVAL; flat_buf = kzalloc(sizeof(*flat_buf), GFP_KERNEL); if (!flat_buf) return -ENOMEM; flat_buf->vaddr = dma_alloc_noncoherent(real_dev, etr_buf->size, &flat_buf->daddr, DMA_FROM_DEVICE, GFP_KERNEL); if (!flat_buf->vaddr) { kfree(flat_buf); return -ENOMEM; } flat_buf->size = etr_buf->size; flat_buf->dev = &drvdata->csdev->dev; etr_buf->hwaddr = flat_buf->daddr; etr_buf->mode = ETR_MODE_FLAT; etr_buf->private = flat_buf; return 0; } static void tmc_etr_free_flat_buf(struct etr_buf *etr_buf) { struct etr_flat_buf *flat_buf = etr_buf->private; if (flat_buf && flat_buf->daddr) { struct device *real_dev = flat_buf->dev->parent; dma_free_noncoherent(real_dev, etr_buf->size, flat_buf->vaddr, flat_buf->daddr, DMA_FROM_DEVICE); } kfree(flat_buf); } static void tmc_etr_sync_flat_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp) { struct etr_flat_buf *flat_buf = etr_buf->private; struct device *real_dev = flat_buf->dev->parent; /* * Adjust the buffer to point to the beginning of the trace data * and update the available trace data. */ etr_buf->offset = rrp - etr_buf->hwaddr; if (etr_buf->full) etr_buf->len = etr_buf->size; else etr_buf->len = rwp - rrp; /* * The driver always starts tracing at the beginning of the buffer, * the only reason why we would get a wrap around is when the buffer * is full. Sync the entire buffer in one go for this case. */ if (etr_buf->offset + etr_buf->len > etr_buf->size) dma_sync_single_for_cpu(real_dev, flat_buf->daddr, etr_buf->size, DMA_FROM_DEVICE); else dma_sync_single_for_cpu(real_dev, flat_buf->daddr + etr_buf->offset, etr_buf->len, DMA_FROM_DEVICE); } static ssize_t tmc_etr_get_data_flat_buf(struct etr_buf *etr_buf, u64 offset, size_t len, char **bufpp) { struct etr_flat_buf *flat_buf = etr_buf->private; *bufpp = (char *)flat_buf->vaddr + offset; /* * tmc_etr_buf_get_data already adjusts the length to handle * buffer wrapping around. */ return len; } static const struct etr_buf_operations etr_flat_buf_ops = { .alloc = tmc_etr_alloc_flat_buf, .free = tmc_etr_free_flat_buf, .sync = tmc_etr_sync_flat_buf, .get_data = tmc_etr_get_data_flat_buf, }; /* * tmc_etr_alloc_sg_buf: Allocate an SG buf @etr_buf. Setup the parameters * appropriately. */ static int tmc_etr_alloc_sg_buf(struct tmc_drvdata *drvdata, struct etr_buf *etr_buf, int node, void **pages) { struct etr_sg_table *etr_table; struct device *dev = &drvdata->csdev->dev; etr_table = tmc_init_etr_sg_table(dev, node, etr_buf->size, pages); if (IS_ERR(etr_table)) return -ENOMEM; etr_buf->hwaddr = etr_table->hwaddr; etr_buf->mode = ETR_MODE_ETR_SG; etr_buf->private = etr_table; return 0; } static void tmc_etr_free_sg_buf(struct etr_buf *etr_buf) { struct etr_sg_table *etr_table = etr_buf->private; if (etr_table) { tmc_free_sg_table(etr_table->sg_table); kfree(etr_table); } } static ssize_t tmc_etr_get_data_sg_buf(struct etr_buf *etr_buf, u64 offset, size_t len, char **bufpp) { struct etr_sg_table *etr_table = etr_buf->private; return tmc_sg_table_get_data(etr_table->sg_table, offset, len, bufpp); } static void tmc_etr_sync_sg_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp) { long r_offset, w_offset; struct etr_sg_table *etr_table = etr_buf->private; struct tmc_sg_table *table = etr_table->sg_table; /* Convert hw address to offset in the buffer */ r_offset = tmc_sg_get_data_page_offset(table, rrp); if (r_offset < 0) { dev_warn(table->dev, "Unable to map RRP %llx to offset\n", rrp); etr_buf->len = 0; return; } w_offset = tmc_sg_get_data_page_offset(table, rwp); if (w_offset < 0) { dev_warn(table->dev, "Unable to map RWP %llx to offset\n", rwp); etr_buf->len = 0; return; } etr_buf->offset = r_offset; if (etr_buf->full) etr_buf->len = etr_buf->size; else etr_buf->len = ((w_offset < r_offset) ? etr_buf->size : 0) + w_offset - r_offset; tmc_sg_table_sync_data_range(table, r_offset, etr_buf->len); } static const struct etr_buf_operations etr_sg_buf_ops = { .alloc = tmc_etr_alloc_sg_buf, .free = tmc_etr_free_sg_buf, .sync = tmc_etr_sync_sg_buf, .get_data = tmc_etr_get_data_sg_buf, }; /* * TMC ETR could be connected to a CATU device, which can provide address * translation service. This is represented by the Output port of the TMC * (ETR) connected to the input port of the CATU. * * Returns : coresight_device ptr for the CATU device if a CATU is found. * : NULL otherwise. */ struct coresight_device * tmc_etr_get_catu_device(struct tmc_drvdata *drvdata) { int i; struct coresight_device *tmp, *etr = drvdata->csdev; if (!IS_ENABLED(CONFIG_CORESIGHT_CATU)) return NULL; for (i = 0; i < etr->pdata->nr_outport; i++) { tmp = etr->pdata->conns[i].child_dev; if (tmp && coresight_is_catu_device(tmp)) return tmp; } return NULL; } EXPORT_SYMBOL_GPL(tmc_etr_get_catu_device); static inline int tmc_etr_enable_catu(struct tmc_drvdata *drvdata, struct etr_buf *etr_buf) { struct coresight_device *catu = tmc_etr_get_catu_device(drvdata); if (catu && helper_ops(catu)->enable) return helper_ops(catu)->enable(catu, etr_buf); return 0; } static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata) { struct coresight_device *catu = tmc_etr_get_catu_device(drvdata); if (catu && helper_ops(catu)->disable) helper_ops(catu)->disable(catu, drvdata->etr_buf); } static const struct etr_buf_operations *etr_buf_ops[] = { [ETR_MODE_FLAT] = &etr_flat_buf_ops, [ETR_MODE_ETR_SG] = &etr_sg_buf_ops, [ETR_MODE_CATU] = NULL, }; void tmc_etr_set_catu_ops(const struct etr_buf_operations *catu) { etr_buf_ops[ETR_MODE_CATU] = catu; } EXPORT_SYMBOL_GPL(tmc_etr_set_catu_ops); void tmc_etr_remove_catu_ops(void) { etr_buf_ops[ETR_MODE_CATU] = NULL; } EXPORT_SYMBOL_GPL(tmc_etr_remove_catu_ops); static inline int tmc_etr_mode_alloc_buf(int mode, struct tmc_drvdata *drvdata, struct etr_buf *etr_buf, int node, void **pages) { int rc = -EINVAL; switch (mode) { case ETR_MODE_FLAT: case ETR_MODE_ETR_SG: case ETR_MODE_CATU: if (etr_buf_ops[mode] && etr_buf_ops[mode]->alloc) rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf, node, pages); if (!rc) etr_buf->ops = etr_buf_ops[mode]; return rc; default: return -EINVAL; } } /* * tmc_alloc_etr_buf: Allocate a buffer use by ETR. * @drvdata : ETR device details. * @size : size of the requested buffer. * @flags : Required properties for the buffer. * @node : Node for memory allocations. * @pages : An optional list of pages. */ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata, ssize_t size, int flags, int node, void **pages) { int rc = -ENOMEM; bool has_etr_sg, has_iommu; bool has_sg, has_catu; struct etr_buf *etr_buf; struct device *dev = &drvdata->csdev->dev; has_etr_sg = tmc_etr_has_cap(drvdata, TMC_ETR_SG); has_iommu = iommu_get_domain_for_dev(dev->parent); has_catu = !!tmc_etr_get_catu_device(drvdata); has_sg = has_catu || has_etr_sg; etr_buf = kzalloc(sizeof(*etr_buf), GFP_KERNEL); if (!etr_buf) return ERR_PTR(-ENOMEM); etr_buf->size = size; /* * If we have to use an existing list of pages, we cannot reliably * use a contiguous DMA memory (even if we have an IOMMU). Otherwise, * we use the contiguous DMA memory if at least one of the following * conditions is true: * a) The ETR cannot use Scatter-Gather. * b) we have a backing IOMMU * c) The requested memory size is smaller (< 1M). * * Fallback to available mechanisms. * */ if (!pages && (!has_sg || has_iommu || size < SZ_1M)) rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata, etr_buf, node, pages); if (rc && has_etr_sg) rc = tmc_etr_mode_alloc_buf(ETR_MODE_ETR_SG, drvdata, etr_buf, node, pages); if (rc && has_catu) rc = tmc_etr_mode_alloc_buf(ETR_MODE_CATU, drvdata, etr_buf, node, pages); if (rc) { kfree(etr_buf); return ERR_PTR(rc); } refcount_set(&etr_buf->refcount, 1); dev_dbg(dev, "allocated buffer of size %ldKB in mode %d\n", (unsigned long)size >> 10, etr_buf->mode); return etr_buf; } static void tmc_free_etr_buf(struct etr_buf *etr_buf) { WARN_ON(!etr_buf->ops || !etr_buf->ops->free); etr_buf->ops->free(etr_buf); kfree(etr_buf); } /* * tmc_etr_buf_get_data: Get the pointer the trace data at @offset * with a maximum of @len bytes. * Returns: The size of the linear data available @pos, with *bufpp * updated to point to the buffer. */ static ssize_t tmc_etr_buf_get_data(struct etr_buf *etr_buf, u64 offset, size_t len, char **bufpp) { /* Adjust the length to limit this transaction to end of buffer */ len = (len < (etr_buf->size - offset)) ? len : etr_buf->size - offset; return etr_buf->ops->get_data(etr_buf, (u64)offset, len, bufpp); } static inline s64 tmc_etr_buf_insert_barrier_packet(struct etr_buf *etr_buf, u64 offset) { ssize_t len; char *bufp; len = tmc_etr_buf_get_data(etr_buf, offset, CORESIGHT_BARRIER_PKT_SIZE, &bufp); if (WARN_ON(len < 0 || len < CORESIGHT_BARRIER_PKT_SIZE)) return -EINVAL; coresight_insert_barrier_packet(bufp); return offset + CORESIGHT_BARRIER_PKT_SIZE; } /* * tmc_sync_etr_buf: Sync the trace buffer availability with drvdata. * Makes sure the trace data is synced to the memory for consumption. * @etr_buf->offset will hold the offset to the beginning of the trace data * within the buffer, with @etr_buf->len bytes to consume. */ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata) { struct etr_buf *etr_buf = drvdata->etr_buf; u64 rrp, rwp; u32 status; rrp = tmc_read_rrp(drvdata); rwp = tmc_read_rwp(drvdata); status = readl_relaxed(drvdata->base + TMC_STS); /* * If there were memory errors in the session, truncate the * buffer. */ if (WARN_ON_ONCE(status & TMC_STS_MEMERR)) { dev_dbg(&drvdata->csdev->dev, "tmc memory error detected, truncating buffer\n"); etr_buf->len = 0; etr_buf->full = false; return; } etr_buf->full = !!(status & TMC_STS_FULL); WARN_ON(!etr_buf->ops || !etr_buf->ops->sync); etr_buf->ops->sync(etr_buf, rrp, rwp); } static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata) { u32 axictl, sts; struct etr_buf *etr_buf = drvdata->etr_buf; CS_UNLOCK(drvdata->base); /* Wait for TMCSReady bit to be set */ tmc_wait_for_tmcready(drvdata); writel_relaxed(etr_buf->size / 4, drvdata->base + TMC_RSZ); writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE); axictl = readl_relaxed(drvdata->base + TMC_AXICTL); axictl &= ~TMC_AXICTL_CLEAR_MASK; axictl |= TMC_AXICTL_PROT_CTL_B1; axictl |= TMC_AXICTL_WR_BURST(drvdata->max_burst_size); axictl |= TMC_AXICTL_AXCACHE_OS; if (tmc_etr_has_cap(drvdata, TMC_ETR_AXI_ARCACHE)) { axictl &= ~TMC_AXICTL_ARCACHE_MASK; axictl |= TMC_AXICTL_ARCACHE_OS; } if (etr_buf->mode == ETR_MODE_ETR_SG) axictl |= TMC_AXICTL_SCT_GAT_MODE; writel_relaxed(axictl, drvdata->base + TMC_AXICTL); tmc_write_dba(drvdata, etr_buf->hwaddr); /* * If the TMC pointers must be programmed before the session, * we have to set it properly (i.e, RRP/RWP to base address and * STS to "not full"). */ if (tmc_etr_has_cap(drvdata, TMC_ETR_SAVE_RESTORE)) { tmc_write_rrp(drvdata, etr_buf->hwaddr); tmc_write_rwp(drvdata, etr_buf->hwaddr); sts = readl_relaxed(drvdata->base + TMC_STS) & ~TMC_STS_FULL; writel_relaxed(sts, drvdata->base + TMC_STS); } writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT | TMC_FFCR_TRIGON_TRIGIN, drvdata->base + TMC_FFCR); writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG); tmc_enable_hw(drvdata); CS_LOCK(drvdata->base); } static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata, struct etr_buf *etr_buf) { int rc; /* Callers should provide an appropriate buffer for use */ if (WARN_ON(!etr_buf)) return -EINVAL; if ((etr_buf->mode == ETR_MODE_ETR_SG) && WARN_ON(!tmc_etr_has_cap(drvdata, TMC_ETR_SG))) return -EINVAL; if (WARN_ON(drvdata->etr_buf)) return -EBUSY; /* * If this ETR is connected to a CATU, enable it before we turn * this on. */ rc = tmc_etr_enable_catu(drvdata, etr_buf); if (rc) return rc; rc = coresight_claim_device(drvdata->csdev); if (!rc) { drvdata->etr_buf = etr_buf; __tmc_etr_enable_hw(drvdata); } return rc; } /* * Return the available trace data in the buffer (starts at etr_buf->offset, * limited by etr_buf->len) from @pos, with a maximum limit of @len, * also updating the @bufpp on where to find it. Since the trace data * starts at anywhere in the buffer, depending on the RRP, we adjust the * @len returned to handle buffer wrapping around. * * We are protected here by drvdata->reading != 0, which ensures the * sysfs_buf stays alive. */ ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata, loff_t pos, size_t len, char **bufpp) { s64 offset; ssize_t actual = len; struct etr_buf *etr_buf = drvdata->sysfs_buf; if (pos + actual > etr_buf->len) actual = etr_buf->len - pos; if (actual <= 0) return actual; /* Compute the offset from which we read the data */ offset = etr_buf->offset + pos; if (offset >= etr_buf->size) offset -= etr_buf->size; return tmc_etr_buf_get_data(etr_buf, offset, actual, bufpp); } static struct etr_buf * tmc_etr_setup_sysfs_buf(struct tmc_drvdata *drvdata) { return tmc_alloc_etr_buf(drvdata, drvdata->size, 0, cpu_to_node(0), NULL); } static void tmc_etr_free_sysfs_buf(struct etr_buf *buf) { if (buf) tmc_free_etr_buf(buf); } static void tmc_etr_sync_sysfs_buf(struct tmc_drvdata *drvdata) { struct etr_buf *etr_buf = drvdata->etr_buf; if (WARN_ON(drvdata->sysfs_buf != etr_buf)) { tmc_etr_free_sysfs_buf(drvdata->sysfs_buf); drvdata->sysfs_buf = NULL; } else { tmc_sync_etr_buf(drvdata); /* * Insert barrier packets at the beginning, if there was * an overflow. */ if (etr_buf->full) tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset); } } static void __tmc_etr_disable_hw(struct tmc_drvdata *drvdata) { CS_UNLOCK(drvdata->base); tmc_flush_and_stop(drvdata); /* * When operating in sysFS mode the content of the buffer needs to be * read before the TMC is disabled. */ if (drvdata->mode == CS_MODE_SYSFS) tmc_etr_sync_sysfs_buf(drvdata); tmc_disable_hw(drvdata); CS_LOCK(drvdata->base); } void tmc_etr_disable_hw(struct tmc_drvdata *drvdata) { __tmc_etr_disable_hw(drvdata); /* Disable CATU device if this ETR is connected to one */ tmc_etr_disable_catu(drvdata); coresight_disclaim_device(drvdata->csdev); /* Reset the ETR buf used by hardware */ drvdata->etr_buf = NULL; } static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev) { int ret = 0; unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); struct etr_buf *sysfs_buf = NULL, *new_buf = NULL, *free_buf = NULL; /* * If we are enabling the ETR from disabled state, we need to make * sure we have a buffer with the right size. The etr_buf is not reset * immediately after we stop the tracing in SYSFS mode as we wait for * the user to collect the data. We may be able to reuse the existing * buffer, provided the size matches. Any allocation has to be done * with the lock released. */ spin_lock_irqsave(&drvdata->spinlock, flags); sysfs_buf = READ_ONCE(drvdata->sysfs_buf); if (!sysfs_buf || (sysfs_buf->size != drvdata->size)) { spin_unlock_irqrestore(&drvdata->spinlock, flags); /* Allocate memory with the locks released */ free_buf = new_buf = tmc_etr_setup_sysfs_buf(drvdata); if (IS_ERR(new_buf)) return PTR_ERR(new_buf); /* Let's try again */ spin_lock_irqsave(&drvdata->spinlock, flags); } if (drvdata->reading || drvdata->mode == CS_MODE_PERF) { ret = -EBUSY; goto out; } /* * In sysFS mode we can have multiple writers per sink. Since this * sink is already enabled no memory is needed and the HW need not be * touched, even if the buffer size has changed. */ if (drvdata->mode == CS_MODE_SYSFS) { atomic_inc(csdev->refcnt); goto out; } /* * If we don't have a buffer or it doesn't match the requested size, * use the buffer allocated above. Otherwise reuse the existing buffer. */ sysfs_buf = READ_ONCE(drvdata->sysfs_buf); if (!sysfs_buf || (new_buf && sysfs_buf->size != new_buf->size)) { free_buf = sysfs_buf; drvdata->sysfs_buf = new_buf; } ret = tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf); if (!ret) { drvdata->mode = CS_MODE_SYSFS; atomic_inc(csdev->refcnt); } out: spin_unlock_irqrestore(&drvdata->spinlock, flags); /* Free memory outside the spinlock if need be */ if (free_buf) tmc_etr_free_sysfs_buf(free_buf); if (!ret) dev_dbg(&csdev->dev, "TMC-ETR enabled\n"); return ret; } /* * alloc_etr_buf: Allocate ETR buffer for use by perf. * The size of the hardware buffer is dependent on the size configured * via sysfs and the perf ring buffer size. We prefer to allocate the * largest possible size, scaling down the size by half until it * reaches a minimum limit (1M), beyond which we give up. */ static struct etr_buf * alloc_etr_buf(struct tmc_drvdata *drvdata, struct perf_event *event, int nr_pages, void **pages, bool snapshot) { int node; struct etr_buf *etr_buf; unsigned long size; node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu); /* * Try to match the perf ring buffer size if it is larger * than the size requested via sysfs. */ if ((nr_pages << PAGE_SHIFT) > drvdata->size) { etr_buf = tmc_alloc_etr_buf(drvdata, ((ssize_t)nr_pages << PAGE_SHIFT), 0, node, NULL); if (!IS_ERR(etr_buf)) goto done; } /* * Else switch to configured size for this ETR * and scale down until we hit the minimum limit. */ size = drvdata->size; do { etr_buf = tmc_alloc_etr_buf(drvdata, size, 0, node, NULL); if (!IS_ERR(etr_buf)) goto done; size /= 2; } while (size >= TMC_ETR_PERF_MIN_BUF_SIZE); return ERR_PTR(-ENOMEM); done: return etr_buf; } static struct etr_buf * get_perf_etr_buf_cpu_wide(struct tmc_drvdata *drvdata, struct perf_event *event, int nr_pages, void **pages, bool snapshot) { int ret; pid_t pid = task_pid_nr(event->owner); struct etr_buf *etr_buf; retry: /* * An etr_perf_buffer is associated with an event and holds a reference * to the AUX ring buffer that was created for that event. In CPU-wide * N:1 mode multiple events (one per CPU), each with its own AUX ring * buffer, share a sink. As such an etr_perf_buffer is created for each * event but a single etr_buf associated with the ETR is shared between * them. The last event in a trace session will copy the content of the * etr_buf to its AUX ring buffer. Ring buffer associated to other * events are simply not used an freed as events are destoyed. We still * need to allocate a ring buffer for each event since we don't know * which event will be last. */ /* * The first thing to do here is check if an etr_buf has already been * allocated for this session. If so it is shared with this event, * otherwise it is created. */ mutex_lock(&drvdata->idr_mutex); etr_buf = idr_find(&drvdata->idr, pid); if (etr_buf) { refcount_inc(&etr_buf->refcount); mutex_unlock(&drvdata->idr_mutex); return etr_buf; } /* If we made it here no buffer has been allocated, do so now. */ mutex_unlock(&drvdata->idr_mutex); etr_buf = alloc_etr_buf(drvdata, event, nr_pages, pages, snapshot); if (IS_ERR(etr_buf)) return etr_buf; /* Now that we have a buffer, add it to the IDR. */ mutex_lock(&drvdata->idr_mutex); ret = idr_alloc(&drvdata->idr, etr_buf, pid, pid + 1, GFP_KERNEL); mutex_unlock(&drvdata->idr_mutex); /* Another event with this session ID has allocated this buffer. */ if (ret == -ENOSPC) { tmc_free_etr_buf(etr_buf); goto retry; } /* The IDR can't allocate room for a new session, abandon ship. */ if (ret == -ENOMEM) { tmc_free_etr_buf(etr_buf); return ERR_PTR(ret); } return etr_buf; } static struct etr_buf * get_perf_etr_buf_per_thread(struct tmc_drvdata *drvdata, struct perf_event *event, int nr_pages, void **pages, bool snapshot) { /* * In per-thread mode the etr_buf isn't shared, so just go ahead * with memory allocation. */ return alloc_etr_buf(drvdata, event, nr_pages, pages, snapshot); } static struct etr_buf * get_perf_etr_buf(struct tmc_drvdata *drvdata, struct perf_event *event, int nr_pages, void **pages, bool snapshot) { if (event->cpu == -1) return get_perf_etr_buf_per_thread(drvdata, event, nr_pages, pages, snapshot); return get_perf_etr_buf_cpu_wide(drvdata, event, nr_pages, pages, snapshot); } static struct etr_perf_buffer * tmc_etr_setup_perf_buf(struct tmc_drvdata *drvdata, struct perf_event *event, int nr_pages, void **pages, bool snapshot) { int node; struct etr_buf *etr_buf; struct etr_perf_buffer *etr_perf; node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu); etr_perf = kzalloc_node(sizeof(*etr_perf), GFP_KERNEL, node); if (!etr_perf) return ERR_PTR(-ENOMEM); etr_buf = get_perf_etr_buf(drvdata, event, nr_pages, pages, snapshot); if (!IS_ERR(etr_buf)) goto done; kfree(etr_perf); return ERR_PTR(-ENOMEM); done: /* * Keep a reference to the ETR this buffer has been allocated for * in order to have access to the IDR in tmc_free_etr_buffer(). */ etr_perf->drvdata = drvdata; etr_perf->etr_buf = etr_buf; return etr_perf; } static void *tmc_alloc_etr_buffer(struct coresight_device *csdev, struct perf_event *event, void **pages, int nr_pages, bool snapshot) { struct etr_perf_buffer *etr_perf; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); etr_perf = tmc_etr_setup_perf_buf(drvdata, event, nr_pages, pages, snapshot); if (IS_ERR(etr_perf)) { dev_dbg(&csdev->dev, "Unable to allocate ETR buffer\n"); return NULL; } etr_perf->pid = task_pid_nr(event->owner); etr_perf->snapshot = snapshot; etr_perf->nr_pages = nr_pages; etr_perf->pages = pages; return etr_perf; } static void tmc_free_etr_buffer(void *config) { struct etr_perf_buffer *etr_perf = config; struct tmc_drvdata *drvdata = etr_perf->drvdata; struct etr_buf *buf, *etr_buf = etr_perf->etr_buf; if (!etr_buf) goto free_etr_perf_buffer; mutex_lock(&drvdata->idr_mutex); /* If we are not the last one to use the buffer, don't touch it. */ if (!refcount_dec_and_test(&etr_buf->refcount)) { mutex_unlock(&drvdata->idr_mutex); goto free_etr_perf_buffer; } /* We are the last one, remove from the IDR and free the buffer. */ buf = idr_remove(&drvdata->idr, etr_perf->pid); mutex_unlock(&drvdata->idr_mutex); /* * Something went very wrong if the buffer associated with this ID * is not the same in the IDR. Leak to avoid use after free. */ if (buf && WARN_ON(buf != etr_buf)) goto free_etr_perf_buffer; tmc_free_etr_buf(etr_perf->etr_buf); free_etr_perf_buffer: kfree(etr_perf); } /* * tmc_etr_sync_perf_buffer: Copy the actual trace data from the hardware * buffer to the perf ring buffer. */ static void tmc_etr_sync_perf_buffer(struct etr_perf_buffer *etr_perf, unsigned long head, unsigned long src_offset, unsigned long to_copy) { long bytes; long pg_idx, pg_offset; char **dst_pages, *src_buf; struct etr_buf *etr_buf = etr_perf->etr_buf; head = PERF_IDX2OFF(head, etr_perf); pg_idx = head >> PAGE_SHIFT; pg_offset = head & (PAGE_SIZE - 1); dst_pages = (char **)etr_perf->pages; while (to_copy > 0) { /* * In one iteration, we can copy minimum of : * 1) what is available in the source buffer, * 2) what is available in the source buffer, before it * wraps around. * 3) what is available in the destination page. * in one iteration. */ if (src_offset >= etr_buf->size) src_offset -= etr_buf->size; bytes = tmc_etr_buf_get_data(etr_buf, src_offset, to_copy, &src_buf); if (WARN_ON_ONCE(bytes <= 0)) break; bytes = min(bytes, (long)(PAGE_SIZE - pg_offset)); memcpy(dst_pages[pg_idx] + pg_offset, src_buf, bytes); to_copy -= bytes; /* Move destination pointers */ pg_offset += bytes; if (pg_offset == PAGE_SIZE) { pg_offset = 0; if (++pg_idx == etr_perf->nr_pages) pg_idx = 0; } /* Move source pointers */ src_offset += bytes; } } /* * tmc_update_etr_buffer : Update the perf ring buffer with the * available trace data. We use software double buffering at the moment. * * TODO: Add support for reusing the perf ring buffer. */ static unsigned long tmc_update_etr_buffer(struct coresight_device *csdev, struct perf_output_handle *handle, void *config) { bool lost = false; unsigned long flags, offset, size = 0; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); struct etr_perf_buffer *etr_perf = config; struct etr_buf *etr_buf = etr_perf->etr_buf; spin_lock_irqsave(&drvdata->spinlock, flags); /* Don't do anything if another tracer is using this sink */ if (atomic_read(csdev->refcnt) != 1) { spin_unlock_irqrestore(&drvdata->spinlock, flags); goto out; } if (WARN_ON(drvdata->perf_buf != etr_buf)) { lost = true; spin_unlock_irqrestore(&drvdata->spinlock, flags); goto out; } CS_UNLOCK(drvdata->base); tmc_flush_and_stop(drvdata); tmc_sync_etr_buf(drvdata); CS_LOCK(drvdata->base); spin_unlock_irqrestore(&drvdata->spinlock, flags); lost = etr_buf->full; offset = etr_buf->offset; size = etr_buf->len; /* * The ETR buffer may be bigger than the space available in the * perf ring buffer (handle->size). If so advance the offset so that we * get the latest trace data. In snapshot mode none of that matters * since we are expected to clobber stale data in favour of the latest * traces. */ if (!etr_perf->snapshot && size > handle->size) { u32 mask = tmc_get_memwidth_mask(drvdata); /* * Make sure the new size is aligned in accordance with the * requirement explained in function tmc_get_memwidth_mask(). */ size = handle->size & mask; offset = etr_buf->offset + etr_buf->len - size; if (offset >= etr_buf->size) offset -= etr_buf->size; lost = true; } /* Insert barrier packets at the beginning, if there was an overflow */ if (lost) tmc_etr_buf_insert_barrier_packet(etr_buf, offset); tmc_etr_sync_perf_buffer(etr_perf, handle->head, offset, size); /* * In snapshot mode we simply increment the head by the number of byte * that were written. User space will figure out how many bytes to get * from the AUX buffer based on the position of the head. */ if (etr_perf->snapshot) handle->head += size; /* * Ensure that the AUX trace data is visible before the aux_head * is updated via perf_aux_output_end(), as expected by the * perf ring buffer. */ smp_wmb(); out: /* * Don't set the TRUNCATED flag in snapshot mode because 1) the * captured buffer is expected to be truncated and 2) a full buffer * prevents the event from being re-enabled by the perf core, * resulting in stale data being send to user space. */ if (!etr_perf->snapshot && lost) perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED); return size; } static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data) { int rc = 0; pid_t pid; unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); struct perf_output_handle *handle = data; struct etr_perf_buffer *etr_perf = etm_perf_sink_config(handle); spin_lock_irqsave(&drvdata->spinlock, flags); /* Don't use this sink if it is already claimed by sysFS */ if (drvdata->mode == CS_MODE_SYSFS) { rc = -EBUSY; goto unlock_out; } if (WARN_ON(!etr_perf || !etr_perf->etr_buf)) { rc = -EINVAL; goto unlock_out; } /* Get a handle on the pid of the process to monitor */ pid = etr_perf->pid; /* Do not proceed if this device is associated with another session */ if (drvdata->pid != -1 && drvdata->pid != pid) { rc = -EBUSY; goto unlock_out; } /* * No HW configuration is needed if the sink is already in * use for this session. */ if (drvdata->pid == pid) { atomic_inc(csdev->refcnt); goto unlock_out; } rc = tmc_etr_enable_hw(drvdata, etr_perf->etr_buf); if (!rc) { /* Associate with monitored process. */ drvdata->pid = pid; drvdata->mode = CS_MODE_PERF; drvdata->perf_buf = etr_perf->etr_buf; atomic_inc(csdev->refcnt); } unlock_out: spin_unlock_irqrestore(&drvdata->spinlock, flags); return rc; } static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode, void *data) { switch (mode) { case CS_MODE_SYSFS: return tmc_enable_etr_sink_sysfs(csdev); case CS_MODE_PERF: return tmc_enable_etr_sink_perf(csdev, data); } /* We shouldn't be here */ return -EINVAL; } static int tmc_disable_etr_sink(struct coresight_device *csdev) { unsigned long flags; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); spin_lock_irqsave(&drvdata->spinlock, flags); if (drvdata->reading) { spin_unlock_irqrestore(&drvdata->spinlock, flags); return -EBUSY; } if (atomic_dec_return(csdev->refcnt)) { spin_unlock_irqrestore(&drvdata->spinlock, flags); return -EBUSY; } /* Complain if we (somehow) got out of sync */ WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); tmc_etr_disable_hw(drvdata); /* Dissociate from monitored process. */ drvdata->pid = -1; drvdata->mode = CS_MODE_DISABLED; /* Reset perf specific data */ drvdata->perf_buf = NULL; spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_dbg(&csdev->dev, "TMC-ETR disabled\n"); return 0; } static const struct coresight_ops_sink tmc_etr_sink_ops = { .enable = tmc_enable_etr_sink, .disable = tmc_disable_etr_sink, .alloc_buffer = tmc_alloc_etr_buffer, .update_buffer = tmc_update_etr_buffer, .free_buffer = tmc_free_etr_buffer, }; const struct coresight_ops tmc_etr_cs_ops = { .sink_ops = &tmc_etr_sink_ops, }; int tmc_read_prepare_etr(struct tmc_drvdata *drvdata) { int ret = 0; unsigned long flags; /* config types are set a boot time and never change */ if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR)) return -EINVAL; spin_lock_irqsave(&drvdata->spinlock, flags); if (drvdata->reading) { ret = -EBUSY; goto out; } /* * We can safely allow reads even if the ETR is operating in PERF mode, * since the sysfs session is captured in mode specific data. * If drvdata::sysfs_data is NULL the trace data has been read already. */ if (!drvdata->sysfs_buf) { ret = -EINVAL; goto out; } /* Disable the TMC if we are trying to read from a running session. */ if (drvdata->mode == CS_MODE_SYSFS) __tmc_etr_disable_hw(drvdata); drvdata->reading = true; out: spin_unlock_irqrestore(&drvdata->spinlock, flags); return ret; } int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata) { unsigned long flags; struct etr_buf *sysfs_buf = NULL; /* config types are set a boot time and never change */ if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR)) return -EINVAL; spin_lock_irqsave(&drvdata->spinlock, flags); /* RE-enable the TMC if need be */ if (drvdata->mode == CS_MODE_SYSFS) { /* * The trace run will continue with the same allocated trace * buffer. Since the tracer is still enabled drvdata::buf can't * be NULL. */ __tmc_etr_enable_hw(drvdata); } else { /* * The ETR is not tracing and the buffer was just read. * As such prepare to free the trace buffer. */ sysfs_buf = drvdata->sysfs_buf; drvdata->sysfs_buf = NULL; } drvdata->reading = false; spin_unlock_irqrestore(&drvdata->spinlock, flags); /* Free allocated memory out side of the spinlock */ if (sysfs_buf) tmc_etr_free_sysfs_buf(sysfs_buf); return 0; }