From: Andrew Jeffery andrew@aj.id.au
[ Upstream commit 6bf4ddbe2b4805f0628922446a7e85e34013cd10 ]
Alignment is a hardware constraint of the LPC2AHB bridge, and misaligned reserved memory will present as corrupted data.
Signed-off-by: Andrew Jeffery andrew@aj.id.au Reviewed-by: Joel Stanley joel@jms.id.au Link: https://lore.kernel.org/r/20191016233950.10100-1-andrew@aj.id.au Signed-off-by: Joel Stanley joel@jms.id.au Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/soc/aspeed/aspeed-lpc-ctrl.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/drivers/soc/aspeed/aspeed-lpc-ctrl.c b/drivers/soc/aspeed/aspeed-lpc-ctrl.c index 01ed21e8bfee5..dd147af494fdf 100644 --- a/drivers/soc/aspeed/aspeed-lpc-ctrl.c +++ b/drivers/soc/aspeed/aspeed-lpc-ctrl.c @@ -4,6 +4,7 @@ */
#include <linux/clk.h> +#include <linux/log2.h> #include <linux/mfd/syscon.h> #include <linux/miscdevice.h> #include <linux/mm.h> @@ -241,6 +242,18 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
lpc_ctrl->mem_size = resource_size(&resm); lpc_ctrl->mem_base = resm.start; + + if (!is_power_of_2(lpc_ctrl->mem_size)) { + dev_err(dev, "Reserved memory size must be a power of 2, got %u\n", + (unsigned int)lpc_ctrl->mem_size); + return -EINVAL; + } + + if (!IS_ALIGNED(lpc_ctrl->mem_base, lpc_ctrl->mem_size)) { + dev_err(dev, "Reserved memory must be naturally aligned for size %u\n", + (unsigned int)lpc_ctrl->mem_size); + return -EINVAL; + } }
lpc_ctrl->regmap = syscon_node_to_regmap(