x86: tangier: Fix off-by-one error when preparing CSRT

Intel iDMA 32-bit controller has 17 bits for the maximum block size value.
Due to nature of the binary number representation the maximum value is
2^17 - 1. The original code misses the latter part in equation.

Fixes: 5e99fde34a77 ("x86: tangier: Populate CSRT for shared DMA controller")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/x86/cpu/tangier/acpi.c b/arch/x86/cpu/tangier/acpi.c
index 362e133cf14858d5f73bbba868fdcf2dccdbfd57..8b128138b0d866dbda9a229c35280d00f381b935 100644 (file)
--- a/arch/x86/cpu/tangier/acpi.c
+++ b/arch/x86/cpu/tangier/acpi.c
@@ -95,7 +95,7 @@ static u32 acpi_fill_csrt_dma(struct acpi_csrt_group *grp)
        si->dma_address_width = 32;
        si->base_request_line = 0;
        si->num_handshake_signals = 16;
-       si->max_block_size = 0x20000;
+       si->max_block_size = 0x1ffff;
 
        return grp->length;
 }