diff options
author | Anton Staaf <robotboy@chromium.org> | 2015-04-08 10:44:40 -0700 |
---|---|---|
committer | ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> | 2015-04-13 20:00:58 +0000 |
commit | 8c0cef260727ba125def62cfd0ef9c09fc9c2172 (patch) | |
tree | 15e9e12056e60a51c360bb939d60c327aec69010 /chip/stm32/usb.c | |
parent | 0016de8250807601f46fb3736f93518155eca95f (diff) | |
download | chrome-ec-8c0cef260727ba125def62cfd0ef9c09fc9c2172.tar.gz |
USB: Fix memcpy routines
The memcpy like routines for moving to and from usb packet
RAM couldn't deal with all unaligned uses, this fixes their
behavior. In particular, a previous caller might assume
that the packet RAM addresses were contiguous and attempt
to break up a call into two separate chunks (as the queue
insertion/removal code does). But this can lead to invalid
pointers passed to these memcpy routines. A much cleaner
solution is to make the packet RAM address space contiguous.
To do so the memcpy routines take packet RAM addresses
instead of AHB address space mapped addresses and
__usb_ram_start needed to change to be of type usb_uint so
that pointer arithmatic on it worked correctly on all platforms,
this also allowed the usb_sram_addr macro to be simplified.
Signed-off-by: Anton Staaf <robotboy@chromium.org>
BRANCH=None
BUG=None
TEST=make buildall -j
Verify that USB still works on Ryu and discovery-stm32f072
Change-Id: I479461f07a3203f1e6e0cf9705f512a5a43c4646
Reviewed-on: https://chromium-review.googlesource.com/264764
Trybot-Ready: Anton Staaf <robotboy@chromium.org>
Tested-by: Anton Staaf <robotboy@chromium.org>
Reviewed-by: Anton Staaf <robotboy@chromium.org>
Commit-Queue: Anton Staaf <robotboy@chromium.org>
Diffstat (limited to 'chip/stm32/usb.c')
-rw-r--r-- | chip/stm32/usb.c | 41 |
1 files changed, 20 insertions, 21 deletions
diff --git a/chip/stm32/usb.c b/chip/stm32/usb.c index ff71b4e582..cb419d998b 100644 --- a/chip/stm32/usb.c +++ b/chip/stm32/usb.c @@ -77,6 +77,8 @@ struct stm32_endpoint btable_ep[USB_EP_COUNT] static usb_uint ep0_buf_tx[USB_MAX_PACKET_SIZE / 2] __usb_ram; static usb_uint ep0_buf_rx[USB_MAX_PACKET_SIZE / 2] __usb_ram; +#define EP0_BUF_TX_SRAM_ADDR ((void *) usb_sram_addr(ep0_buf_tx)) + static int set_addr; /* remaining size of descriptor data to transfer */ static int desc_left; @@ -155,7 +157,7 @@ static void ep0_rx(void) desc_ptr = desc + USB_MAX_PACKET_SIZE; len = USB_MAX_PACKET_SIZE; } - memcpy_to_usbram(ep0_buf_tx, desc, len); + memcpy_to_usbram(EP0_BUF_TX_SRAM_ADDR, desc, len); if (type == USB_DT_CONFIGURATION) /* set the real descriptor size */ ep0_buf_tx[1] = USB_DESC_SIZE; @@ -166,7 +168,7 @@ static void ep0_rx(void) } else if (req == (USB_DIR_IN | (USB_REQ_GET_STATUS << 8))) { uint16_t zero = 0; /* Get status */ - memcpy_to_usbram(ep0_buf_tx, (void *)&zero, 2); + memcpy_to_usbram(EP0_BUF_TX_SRAM_ADDR, (void *)&zero, 2); btable_ep[0].tx_count = 2; STM32_TOGGLE_EP(0, EP_TX_RX_MASK, EP_TX_RX_VALID, EP_STATUS_OUT /*null OUT transaction */); @@ -208,7 +210,7 @@ static void ep0_tx(void) if (desc_ptr) { /* we have an on-going descriptor transfer */ int len = MIN(desc_left, USB_MAX_PACKET_SIZE); - memcpy_to_usbram(ep0_buf_tx, desc_ptr, len); + memcpy_to_usbram(EP0_BUF_TX_SRAM_ADDR, desc_ptr, len); btable_ep[0].tx_count = len; desc_left -= len; desc_ptr += len; @@ -346,21 +348,15 @@ int usb_is_enabled(void) void *memcpy_to_usbram(void *dest, const void *src, size_t n) { + int unaligned = (((uintptr_t) dest) & 1); + usb_uint *d = &__usb_ram_start[((uintptr_t) dest) / 2]; + uint8_t *s = (uint8_t *) src; + int i; + /* - * The d pointer needs to be volatile to prevent GCC from possibly - * breaking writes to the USB packet RAM into multiple 16-bit writes, - * which, due to the way the AHB2APB bridge works would clobber what - * we write with 32-bit extensions of the 16-bit writes. + * Handle unaligned leading byte via read/modify/write. */ - int i; - uint8_t *s = (uint8_t *) src; - usb_uint volatile *d = (usb_uint volatile *)((uintptr_t) dest & ~1); - - if ((((uintptr_t) dest) & 1) && n) { - /* - * The first destination byte is not aligned, perform a read/ - * modify/write. - */ + if (unaligned && n) { *d = (*d & ~0xff00) | (*s << 8); n--; s++; @@ -382,13 +378,16 @@ void *memcpy_to_usbram(void *dest, const void *src, size_t n) void *memcpy_from_usbram(void *dest, const void *src, size_t n) { - int i; - usb_uint *s = (usb_uint *)((uintptr_t) src & ~1); - uint8_t *d = (uint8_t *) dest; + int unaligned = (((uintptr_t) src) & 1); + usb_uint const *s = &__usb_ram_start[((uintptr_t) src) / 2]; + uint8_t *d = (uint8_t *) dest; + int i; - if ((((uintptr_t) src) & 1) && n) { - *d++ = *s++ >> 8; + if (unaligned && n) { + *d = *s >> 8; n--; + s++; + d++; } for (i = 0; i < n / 2; i++) { |