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Stephen Boyd authored
The inline assembly differences for v6 vs. v7 in the hvc_dcc driver are purely optimizations. On a v7 processor, an mrc with the pc sets the condition codes to the 28-31 bits of the register being read. It just so happens that the TX/RX full bits the DCC driver is testing for are high enough in the register to be put into the condition codes. On a v6 processor, this "feature" isn't implemented and thus we have to do the usual read, mask, test operations to check for TX/RX full. Since we already test the RX/TX full bits before calling __dcc_getchar() and __dcc_putchar() we don't actually need to do anything special for v7 over v6. The only difference is in hvc_dcc_get_chars(). We would test RX full, poll RX full, and then read a character from the buffer, whereas now we will test RX full, read a character from the buffer, and then test RX full again for the second iteration of the loop. It doesn't seem possible for the buffer to go from full to empty between testing the RX full and reading a character. Therefore, replace the v7 versions with the v6 versions and everything works the same. Acked-by:
Tony Lindgren <tony@atomide.com> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by:
Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Daniel Walker <dwalker@codeaurora.org> Signed-off-by:
Stephen Boyd <sboyd@codeaurora.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@suse.de>
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