From 8c9e06e64768665503e778088a39ecff3a6f2e0c Mon Sep 17 00:00:00 2001 From: Nicolas Schichan Date: Thu, 28 May 2015 10:40:12 +0200 Subject: bus: mvebu-mbus: do not set WIN_CTRL_SYNCBARRIER on non io-coherent platforms. Commit a0b5cd4ac2d6 ("bus: mvebu-mbus: use automatic I/O synchronization barriers") enabled the usage of automatic I/O synchronization barriers by enabling bit WIN_CTRL_SYNCBARRIER in the control registers of MBus windows, but on non io-coherent platforms (orion5x, kirkwood and dove) the WIN_CTRL_SYNCBARRIER bit in the window control register is either reserved (all windows except 6 and 7) or enables read-only protection (windows 6 and 7). Signed-off-by: Nicolas Schichan Reviewed-by: Thomas Petazzoni Cc: # v4.0+ Fixes: a0b5cd4ac2d6 ("bus: mvebu-mbus: use automatic I/O synchronization barriers") Signed-off-by: Thomas Petazzoni Signed-off-by: Gregory CLEMENT --- drivers/bus/mvebu-mbus.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/bus') diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c index fb9ec6221730..7fa4510dfbe4 100644 --- a/drivers/bus/mvebu-mbus.c +++ b/drivers/bus/mvebu-mbus.c @@ -70,6 +70,7 @@ */ #define WIN_CTRL_OFF 0x0000 #define WIN_CTRL_ENABLE BIT(0) +/* Only on HW I/O coherency capable platforms */ #define WIN_CTRL_SYNCBARRIER BIT(1) #define WIN_CTRL_TGT_MASK 0xf0 #define WIN_CTRL_TGT_SHIFT 4 @@ -323,8 +324,9 @@ static int mvebu_mbus_setup_window(struct mvebu_mbus_state *mbus, ctrl = ((size - 1) & WIN_CTRL_SIZE_MASK) | (attr << WIN_CTRL_ATTR_SHIFT) | (target << WIN_CTRL_TGT_SHIFT) | - WIN_CTRL_SYNCBARRIER | WIN_CTRL_ENABLE; + if (mbus->hw_io_coherency) + ctrl |= WIN_CTRL_SYNCBARRIER; writel(base & WIN_BASE_LOW, addr + WIN_BASE_OFF); writel(ctrl, addr + WIN_CTRL_OFF); -- cgit v1.2.3 From 885dbd154b2f2ee305cec6fd0a162e1a77ae2b06 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 28 May 2015 10:40:13 +0200 Subject: Revert "bus: mvebu-mbus: make sure SDRAM CS for DMA don't overlap the MBus bridge window" This reverts commit 1737cac69369 ("bus: mvebu-mbus: make sure SDRAM CS for DMA don't overlap the MBus bridge window"), because it breaks DMA on platforms having more than 2 GB of RAM. This commit changed the information reported to DMA masters device drivers through the mv_mbus_dram_info() function so that the returned DRAM ranges do not overlap with I/O windows. This was necessary as a preparation to support the new CESA Crypto Engine driver, which will use DMA for cryptographic operations. But since it does DMA with the SRAM which is mapped as an I/O window, having DRAM ranges overlapping with I/O windows was problematic. To solve this, the above mentioned commit changed the mvebu-mbus to adjust the DRAM ranges so that they don't overlap with the I/O windows. However, by doing this, we re-adjust the DRAM ranges in a way that makes them have a size that is no longer a power of two. While this is perfectly fine for the Crypto Engine, which supports DRAM ranges with a granularity of 64 KB, it breaks basically all other DMA masters, which expect power of two sizes for the DRAM ranges. Due to this, if the installed system memory is 4 GB, in two chip-selects of 2 GB, the second DRAM range will be reduced from 2 GB to a little bit less than 2 GB to not overlap with the I/O windows, in a way that results in a DRAM range that doesn't have a power of two size. This means that whenever you do a DMA transfer with an address located in the [ 2 GB ; 4 GB ] area, it will freeze the system. Any serious DMA activity like simply running: for i in $(seq 1 64) ; do dd if=/dev/urandom of=file$i bs=1M count=16 ; done in an ext3 partition mounted over a SATA drive will freeze the system. Since the new CESA crypto driver that uses DMA has not been merged yet, the easiest fix is to simply revert this commit. A follow-up commit will introduce a different solution for the CESA crypto driver. Signed-off-by: Thomas Petazzoni Fixes: 1737cac69369 ("bus: mvebu-mbus: make sure SDRAM CS for DMA don't overlap the MBus bridge window") Cc: # v4.0+ Signed-off-by: Gregory CLEMENT --- drivers/bus/mvebu-mbus.c | 105 ++++++++--------------------------------------- 1 file changed, 16 insertions(+), 89 deletions(-) (limited to 'drivers/bus') diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c index 7fa4510dfbe4..6f047dcb94c2 100644 --- a/drivers/bus/mvebu-mbus.c +++ b/drivers/bus/mvebu-mbus.c @@ -58,7 +58,6 @@ #include #include #include -#include /* * DDR target is the same on all platforms. @@ -103,9 +102,7 @@ /* Relative to mbusbridge_base */ #define MBUS_BRIDGE_CTRL_OFF 0x0 -#define MBUS_BRIDGE_SIZE_MASK 0xffff0000 #define MBUS_BRIDGE_BASE_OFF 0x4 -#define MBUS_BRIDGE_BASE_MASK 0xffff0000 /* Maximum number of windows, for all known platforms */ #define MBUS_WINS_MAX 20 @@ -579,106 +576,36 @@ static unsigned int armada_xp_mbus_win_remap_offset(int win) return MVEBU_MBUS_NO_REMAP; } -/* - * Use the memblock information to find the MBus bridge hole in the - * physical address space. - */ -static void __init -mvebu_mbus_find_bridge_hole(uint64_t *start, uint64_t *end) -{ - struct memblock_region *r; - uint64_t s = 0; - - for_each_memblock(memory, r) { - /* - * This part of the memory is above 4 GB, so we don't - * care for the MBus bridge hole. - */ - if (r->base >= 0x100000000) - continue; - - /* - * The MBus bridge hole is at the end of the RAM under - * the 4 GB limit. - */ - if (r->base + r->size > s) - s = r->base + r->size; - } - - *start = s; - *end = 0x100000000; -} - static void __init mvebu_mbus_default_setup_cpu_target(struct mvebu_mbus_state *mbus) { int i; int cs; - uint64_t mbus_bridge_base, mbus_bridge_end; mvebu_mbus_dram_info.mbus_dram_target_id = TARGET_DDR; - mvebu_mbus_find_bridge_hole(&mbus_bridge_base, &mbus_bridge_end); - for (i = 0, cs = 0; i < 4; i++) { - u64 base = readl(mbus->sdramwins_base + DDR_BASE_CS_OFF(i)); - u64 size = readl(mbus->sdramwins_base + DDR_SIZE_CS_OFF(i)); - u64 end; - struct mbus_dram_window *w; - - /* Ignore entries that are not enabled */ - if (!(size & DDR_SIZE_ENABLED)) - continue; - - /* - * Ignore entries whose base address is above 2^32, - * since devices cannot DMA to such high addresses - */ - if (base & DDR_BASE_CS_HIGH_MASK) - continue; - - base = base & DDR_BASE_CS_LOW_MASK; - size = (size | ~DDR_SIZE_MASK) + 1; - end = base + size; - - /* - * Adjust base/size of the current CS to make sure it - * doesn't overlap with the MBus bridge hole. This is - * particularly important for devices that do DMA from - * DRAM to a SRAM mapped in a MBus window, such as the - * CESA cryptographic engine. - */ + u32 base = readl(mbus->sdramwins_base + DDR_BASE_CS_OFF(i)); + u32 size = readl(mbus->sdramwins_base + DDR_SIZE_CS_OFF(i)); /* - * The CS is fully enclosed inside the MBus bridge - * area, so ignore it. + * We only take care of entries for which the chip + * select is enabled, and that don't have high base + * address bits set (devices can only access the first + * 32 bits of the memory). */ - if (base >= mbus_bridge_base && end <= mbus_bridge_end) - continue; + if ((size & DDR_SIZE_ENABLED) && + !(base & DDR_BASE_CS_HIGH_MASK)) { + struct mbus_dram_window *w; - /* - * Beginning of CS overlaps with end of MBus, raise CS - * base address, and shrink its size. - */ - if (base >= mbus_bridge_base && end > mbus_bridge_end) { - size -= mbus_bridge_end - base; - base = mbus_bridge_end; + w = &mvebu_mbus_dram_info.cs[cs++]; + w->cs_index = i; + w->mbus_attr = 0xf & ~(1 << i); + if (mbus->hw_io_coherency) + w->mbus_attr |= ATTR_HW_COHERENCY; + w->base = base & DDR_BASE_CS_LOW_MASK; + w->size = (size | ~DDR_SIZE_MASK) + 1; } - - /* - * End of CS overlaps with beginning of MBus, shrink - * CS size. - */ - if (base < mbus_bridge_base && end > mbus_bridge_base) - size -= end - mbus_bridge_base; - - w = &mvebu_mbus_dram_info.cs[cs++]; - w->cs_index = i; - w->mbus_attr = 0xf & ~(1 << i); - if (mbus->hw_io_coherency) - w->mbus_attr |= ATTR_HW_COHERENCY; - w->base = base; - w->size = size; } mvebu_mbus_dram_info.num_cs = cs; } -- cgit v1.2.3 From bfa1ce5f38938cc9e6c7f2d1011f88eba2b9e2b2 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 28 May 2015 11:40:54 +0200 Subject: bus: mvebu-mbus: add mv_mbus_dram_info_nooverlap() This commit introduces a variant of the mv_mbus_dram_info() function called mv_mbus_dram_info_nooverlap(). Both functions are used by Marvell drivers supporting devices doing DMA, and provide them a description the DRAM ranges that they need to configure their DRAM windows. The ranges provided by the mv_mbus_dram_info() function may overlap with the I/O windows if there is a lot (>= 4 GB) of RAM installed. This is not a problem for most of the DMA masters, except for the upcoming new CESA crypto driver because it does DMA to the SRAM, which is mapped through an I/O window. For this unit, we need to have DRAM ranges that do not overlap with the I/O windows. A first implementation done in commit 1737cac69369 ("bus: mvebu-mbus: make sure SDRAM CS for DMA don't overlap the MBus bridge window"), changed the information returned by mv_mbus_dram_info() to match this requirement. However, it broke the requirement of the other DMA masters than the DRAM ranges should have power of two sizes. To solve this situation, this commit introduces a new mv_mbus_dram_info_nooverlap() function, which returns the same information as mv_mbus_dram_info(), but guaranteed to not overlap with the I/O windows. In the end, it gives us two variants of the mv_mbus_dram_info*() functions: - The normal one, mv_mbus_dram_info(), which has been around for many years. This function returns the raw DRAM ranges, which are guaranteed to use power of two sizes, but will overlap with I/O windows. This function will therefore be used by all DMA masters (SATA, XOR, Ethernet, etc.) except the CESA crypto driver. - The new 'nooverlap' variant, mv_mbus_dram_info_nooverlap(). This function returns DRAM ranges after they have been "tweaked" to make sure they don't overlap with I/O windows. By doing this tweaking, we remove the power of two size guarantee. This variant will be used by the new CESA crypto driver. Signed-off-by: Thomas Petazzoni Signed-off-by: Gregory CLEMENT --- drivers/bus/mvebu-mbus.c | 117 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mbus.h | 5 ++ 2 files changed, 122 insertions(+) (limited to 'drivers/bus') diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c index 6f047dcb94c2..c43c3d2baf73 100644 --- a/drivers/bus/mvebu-mbus.c +++ b/drivers/bus/mvebu-mbus.c @@ -57,6 +57,7 @@ #include #include #include +#include #include /* @@ -152,13 +153,39 @@ struct mvebu_mbus_state { static struct mvebu_mbus_state mbus_state; +/* + * We provide two variants of the mv_mbus_dram_info() function: + * + * - The normal one, where the described DRAM ranges may overlap with + * the I/O windows, but for which the DRAM ranges are guaranteed to + * have a power of two size. Such ranges are suitable for the DMA + * masters that only DMA between the RAM and the device, which is + * actually all devices except the crypto engines. + * + * - The 'nooverlap' one, where the described DRAM ranges are + * guaranteed to not overlap with the I/O windows, but for which the + * DRAM ranges will not have power of two sizes. They will only be + * aligned on a 64 KB boundary, and have a size multiple of 64 + * KB. Such ranges are suitable for the DMA masters that DMA between + * the crypto SRAM (which is mapped through an I/O window) and a + * device. This is the case for the crypto engines. + */ + static struct mbus_dram_target_info mvebu_mbus_dram_info; +static struct mbus_dram_target_info mvebu_mbus_dram_info_nooverlap; + const struct mbus_dram_target_info *mv_mbus_dram_info(void) { return &mvebu_mbus_dram_info; } EXPORT_SYMBOL_GPL(mv_mbus_dram_info); +const struct mbus_dram_target_info *mv_mbus_dram_info_nooverlap(void) +{ + return &mvebu_mbus_dram_info_nooverlap; +} +EXPORT_SYMBOL_GPL(mv_mbus_dram_info_nooverlap); + /* Checks whether the given window has remap capability */ static bool mvebu_mbus_window_is_remappable(struct mvebu_mbus_state *mbus, const int win) @@ -576,6 +603,95 @@ static unsigned int armada_xp_mbus_win_remap_offset(int win) return MVEBU_MBUS_NO_REMAP; } +/* + * Use the memblock information to find the MBus bridge hole in the + * physical address space. + */ +static void __init +mvebu_mbus_find_bridge_hole(uint64_t *start, uint64_t *end) +{ + struct memblock_region *r; + uint64_t s = 0; + + for_each_memblock(memory, r) { + /* + * This part of the memory is above 4 GB, so we don't + * care for the MBus bridge hole. + */ + if (r->base >= 0x100000000ULL) + continue; + + /* + * The MBus bridge hole is at the end of the RAM under + * the 4 GB limit. + */ + if (r->base + r->size > s) + s = r->base + r->size; + } + + *start = s; + *end = 0x100000000ULL; +} + +/* + * This function fills in the mvebu_mbus_dram_info_nooverlap data + * structure, by looking at the mvebu_mbus_dram_info data, and + * removing the parts of it that overlap with I/O windows. + */ +static void __init +mvebu_mbus_setup_cpu_target_nooverlap(struct mvebu_mbus_state *mbus) +{ + uint64_t mbus_bridge_base, mbus_bridge_end; + int cs_nooverlap = 0; + int i; + + mvebu_mbus_find_bridge_hole(&mbus_bridge_base, &mbus_bridge_end); + + for (i = 0; i < mvebu_mbus_dram_info.num_cs; i++) { + struct mbus_dram_window *w; + u64 base, size, end; + + w = &mvebu_mbus_dram_info.cs[i]; + base = w->base; + size = w->size; + end = base + size; + + /* + * The CS is fully enclosed inside the MBus bridge + * area, so ignore it. + */ + if (base >= mbus_bridge_base && end <= mbus_bridge_end) + continue; + + /* + * Beginning of CS overlaps with end of MBus, raise CS + * base address, and shrink its size. + */ + if (base >= mbus_bridge_base && end > mbus_bridge_end) { + size -= mbus_bridge_end - base; + base = mbus_bridge_end; + } + + /* + * End of CS overlaps with beginning of MBus, shrink + * CS size. + */ + if (base < mbus_bridge_base && end > mbus_bridge_base) + size -= end - mbus_bridge_base; + + w = &mvebu_mbus_dram_info_nooverlap.cs[cs_nooverlap++]; + w->cs_index = i; + w->mbus_attr = 0xf & ~(1 << i); + if (mbus->hw_io_coherency) + w->mbus_attr |= ATTR_HW_COHERENCY; + w->base = base; + w->size = size; + } + + mvebu_mbus_dram_info_nooverlap.mbus_dram_target_id = TARGET_DDR; + mvebu_mbus_dram_info_nooverlap.num_cs = cs_nooverlap; +} + static void __init mvebu_mbus_default_setup_cpu_target(struct mvebu_mbus_state *mbus) { @@ -964,6 +1080,7 @@ static int __init mvebu_mbus_common_init(struct mvebu_mbus_state *mbus, mvebu_mbus_disable_window(mbus, win); mbus->soc->setup_cpu_target(mbus); + mvebu_mbus_setup_cpu_target_nooverlap(mbus); if (is_coherent) writel(UNIT_SYNC_BARRIER_ALL, diff --git a/include/linux/mbus.h b/include/linux/mbus.h index 611b69fa8594..1f7bc630d225 100644 --- a/include/linux/mbus.h +++ b/include/linux/mbus.h @@ -54,11 +54,16 @@ struct mbus_dram_target_info */ #ifdef CONFIG_PLAT_ORION extern const struct mbus_dram_target_info *mv_mbus_dram_info(void); +extern const struct mbus_dram_target_info *mv_mbus_dram_info_nooverlap(void); #else static inline const struct mbus_dram_target_info *mv_mbus_dram_info(void) { return NULL; } +static inline const struct mbus_dram_target_info *mv_mbus_dram_info_nooverlap(void) +{ + return NULL; +} #endif int mvebu_mbus_save_cpu_target(u32 *store_addr); -- cgit v1.2.3