Thread (51 messages) 51 messages, 6 authors, 2021-09-24

Re: [PATCH V3 16/22] LoongArch: Add misc common routines

From: Christoph Hellwig <hch@infradead.org>
Date: 2021-09-17 06:12:57
Also in: linux-arch, lkml

+
+/*
+ * Change "struct page" to physical address.
+ */
+#define page_to_phys(page)	((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
Why is this using a dma_addr_t?  phys_addr_t would be the right type
here.
+
+extern void __init __iomem *early_ioremap(u64 phys_addr, unsigned long size);
+extern void __init early_iounmap(void __iomem *addr, unsigned long size);
+
+#define early_memremap early_ioremap
+#define early_memunmap early_iounmap
+
+static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
+					 unsigned long prot_val)
+{
+	if (prot_val == _CACHE_CC)
+		return (void __iomem *)(unsigned long)(CAC_BASE + offset);
+	else
+		return (void __iomem *)(unsigned long)(UNCAC_BASE + offset);
+}
There is no real need for this ioremap_prot multiplexer
+/*
+ * ioremap_cache -  map bus memory into CPU space
+ * @offset:	    bus address of the memory
+ * @size:	    size of the resource to map
+ *
+ * ioremap_cache performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address.
+ *
+ * This version of ioremap ensures that the memory is marked cachable by
+ * the CPU.  Also enables full write-combining.	 Useful for some
+ * memory-like regions on I/O busses.
+ */
+#define ioremap_cache(offset, size)				\
+	ioremap_prot((offset), (size), _CACHE_CC)
Please don't add ioremap_cache to new ports.
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