From 9347359ad0aeeed16bf8c2d4576a2c40edaa9c85 Mon Sep 17 00:00:00 2001 From: Shanker Donthineni Date: Mon, 6 Jun 2016 18:17:30 -0500 Subject: [PATCH] irqchip/gicv3-its: Split its_alloc_tables() into two functions The function is getting out of control, it has too many goto statements and would be too complicated for adding a feature two-level device table. So, it is time for us to cleanup and move some of the logic to a separate function without affecting the existing functionality. Signed-off-by: Shanker Donthineni Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its.c | 242 +++++++++++++++-------------- include/linux/irqchip/arm-gic-v3.h | 1 + 2 files changed, 127 insertions(+), 116 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 5cfa29991eed..146189b1b587 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -56,13 +56,14 @@ struct its_collection { }; /* - * The ITS_BASER structure - contains memory information and cached - * value of BASER register configuration. + * The ITS_BASER structure - contains memory information, cached + * value of BASER register configuration and ITS page size. */ struct its_baser { void *base; u64 val; u32 order; + u32 psz; }; /* @@ -840,6 +841,110 @@ static void its_write_baser(struct its_node *its, struct its_baser *baser, baser->val = its_read_baser(its, baser); } +static int its_setup_baser(struct its_node *its, struct its_baser *baser, + u64 cache, u64 shr, u32 psz, u32 order) +{ + u64 val = its_read_baser(its, baser); + u64 esz = GITS_BASER_ENTRY_SIZE(val); + u64 type = GITS_BASER_TYPE(val); + u32 alloc_pages; + void *base; + u64 tmp; + +retry_alloc_baser: + alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz); + if (alloc_pages > GITS_BASER_PAGES_MAX) { + pr_warn("ITS@%pa: %s too large, reduce ITS pages %u->%u\n", + &its->phys_base, its_base_type_string[type], + alloc_pages, GITS_BASER_PAGES_MAX); + alloc_pages = GITS_BASER_PAGES_MAX; + order = get_order(GITS_BASER_PAGES_MAX * psz); + } + + base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); + if (!base) + return -ENOMEM; + +retry_baser: + val = (virt_to_phys(base) | + (type << GITS_BASER_TYPE_SHIFT) | + ((esz - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) | + ((alloc_pages - 1) << GITS_BASER_PAGES_SHIFT) | + cache | + shr | + GITS_BASER_VALID); + + switch (psz) { + case SZ_4K: + val |= GITS_BASER_PAGE_SIZE_4K; + break; + case SZ_16K: + val |= GITS_BASER_PAGE_SIZE_16K; + break; + case SZ_64K: + val |= GITS_BASER_PAGE_SIZE_64K; + break; + } + + its_write_baser(its, baser, val); + tmp = baser->val; + + if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) { + /* + * Shareability didn't stick. Just use + * whatever the read reported, which is likely + * to be the only thing this redistributor + * supports. If that's zero, make it + * non-cacheable as well. + */ + shr = tmp & GITS_BASER_SHAREABILITY_MASK; + if (!shr) { + cache = GITS_BASER_nC; + __flush_dcache_area(base, PAGE_ORDER_TO_SIZE(order)); + } + goto retry_baser; + } + + if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) { + /* + * Page size didn't stick. Let's try a smaller + * size and retry. If we reach 4K, then + * something is horribly wrong... + */ + free_pages((unsigned long)base, order); + baser->base = NULL; + + switch (psz) { + case SZ_16K: + psz = SZ_4K; + goto retry_alloc_baser; + case SZ_64K: + psz = SZ_16K; + goto retry_alloc_baser; + } + } + + if (val != tmp) { + pr_err("ITS@%pa: %s doesn't stick: %lx %lx\n", + &its->phys_base, its_base_type_string[type], + (unsigned long) val, (unsigned long) tmp); + free_pages((unsigned long)base, order); + return -ENXIO; + } + + baser->order = order; + baser->base = base; + baser->psz = psz; + + pr_info("ITS@%pa: allocated %d %s @%lx (psz %dK, shr %d)\n", + &its->phys_base, (int)(PAGE_ORDER_TO_SIZE(order) / esz), + its_base_type_string[type], + (unsigned long)virt_to_phys(base), + psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT); + + return 0; +} + static void its_parse_baser_device(struct its_node *its, struct its_baser *baser, u32 *order) { @@ -879,25 +984,20 @@ static void its_free_tables(struct its_node *its) static int its_alloc_tables(const char *node_name, struct its_node *its) { - int err; - int i; - int psz = SZ_64K; + u64 typer = readq_relaxed(its->base + GITS_TYPER); + u32 ids = GITS_TYPER_DEVBITS(typer); u64 shr = GITS_BASER_InnerShareable; - u64 cache; - u64 typer; - u32 ids; + u64 cache = GITS_BASER_WaWb; + u32 psz = SZ_64K; + int err, i; if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_22375) { /* - * erratum 22375: only alloc 8MB table size - * erratum 24313: ignore memory access type - */ - cache = 0; - ids = 0x14; /* 20 bits, 8MB */ - } else { - cache = GITS_BASER_WaWb; - typer = readq_relaxed(its->base + GITS_TYPER); - ids = GITS_TYPER_DEVBITS(typer); + * erratum 22375: only alloc 8MB table size + * erratum 24313: ignore memory access type + */ + cache = GITS_BASER_nCnB; + ids = 0x14; /* 20 bits, 8MB */ } its->device_ids = ids; @@ -906,11 +1006,7 @@ static int its_alloc_tables(const char *node_name, struct its_node *its) struct its_baser *baser = its->tables + i; u64 val = its_read_baser(its, baser); u64 type = GITS_BASER_TYPE(val); - u64 entry_size = GITS_BASER_ENTRY_SIZE(val); - int order = get_order(psz); - int alloc_pages; - u64 tmp; - void *base; + u32 order = get_order(psz); if (type == GITS_BASER_TYPE_NONE) continue; @@ -918,105 +1014,19 @@ static int its_alloc_tables(const char *node_name, struct its_node *its) if (type == GITS_BASER_TYPE_DEVICE) its_parse_baser_device(its, baser, &order); -retry_alloc_baser: - alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz); - if (alloc_pages > GITS_BASER_PAGES_MAX) { - alloc_pages = GITS_BASER_PAGES_MAX; - order = get_order(GITS_BASER_PAGES_MAX * psz); - pr_warn("%s: Device Table too large, reduce its page order to %u (%u pages)\n", - node_name, order, alloc_pages); - } - - base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); - if (!base) { - err = -ENOMEM; - goto out_free; - } - - its->tables[i].base = base; - its->tables[i].order = order; - -retry_baser: - val = (virt_to_phys(base) | - (type << GITS_BASER_TYPE_SHIFT) | - ((entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) | - cache | - shr | - GITS_BASER_VALID); - - switch (psz) { - case SZ_4K: - val |= GITS_BASER_PAGE_SIZE_4K; - break; - case SZ_16K: - val |= GITS_BASER_PAGE_SIZE_16K; - break; - case SZ_64K: - val |= GITS_BASER_PAGE_SIZE_64K; - break; - } - - val |= alloc_pages - 1; - - its_write_baser_cache(its, baser, val); - tmp = baser->val; - - if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) { - /* - * Shareability didn't stick. Just use - * whatever the read reported, which is likely - * to be the only thing this redistributor - * supports. If that's zero, make it - * non-cacheable as well. - */ - shr = tmp & GITS_BASER_SHAREABILITY_MASK; - if (!shr) { - cache = GITS_BASER_nC; - __flush_dcache_area(base, PAGE_ORDER_TO_SIZE(order)); - } - goto retry_baser; - } - - if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) { - /* - * Page size didn't stick. Let's try a smaller - * size and retry. If we reach 4K, then - * something is horribly wrong... - */ - free_pages((unsigned long)base, order); - its->tables[i].base = NULL; - - switch (psz) { - case SZ_16K: - psz = SZ_4K; - goto retry_alloc_baser; - case SZ_64K: - psz = SZ_16K; - goto retry_alloc_baser; - } - } - - if (val != tmp) { - pr_err("ITS: %s: GITS_BASER%d doesn't stick: %lx %lx\n", - node_name, i, - (unsigned long) val, (unsigned long) tmp); - err = -ENXIO; - goto out_free; + err = its_setup_baser(its, baser, cache, shr, psz, order); + if (err < 0) { + its_free_tables(its); + return err; } - pr_info("ITS: allocated %d %s @%lx (psz %dK, shr %d)\n", - (int)(PAGE_ORDER_TO_SIZE(order) / entry_size), - its_base_type_string[type], - (unsigned long)virt_to_phys(base), - psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT); + /* Update settings which will be used for next BASERn */ + psz = baser->psz; + cache = baser->val & GITS_BASER_CACHEABILITY_MASK; + shr = baser->val & GITS_BASER_SHAREABILITY_MASK; } return 0; - -out_free: - its_free_tables(its); - - return err; } static int its_alloc_collections(struct its_node *its) diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index dc493e0f0ff7..01cf171ef97d 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -228,6 +228,7 @@ #define GITS_BASER_PAGE_SIZE_64K (2UL << GITS_BASER_PAGE_SIZE_SHIFT) #define GITS_BASER_PAGE_SIZE_MASK (3UL << GITS_BASER_PAGE_SIZE_SHIFT) #define GITS_BASER_PAGES_MAX 256 +#define GITS_BASER_PAGES_SHIFT (0) #define GITS_BASER_TYPE_NONE 0 #define GITS_BASER_TYPE_DEVICE 1 -- 2.20.1