1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ti/k3-cppi-desc-pool.c b/drivers/net/ethernet/ti/k3-cppi-desc-pool.c
new file mode 100644
index 000000000000..ad7cfc1316ce
--- /dev/null
+++ b/drivers/net/ethernet/ti/k3-cppi-desc-pool.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0
+/* TI K3 CPPI5 descriptors pool API
+ *
+ * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/genalloc.h>
+#include <linux/kernel.h>
+
+#include "k3-cppi-desc-pool.h"
+
+struct k3_cppi_desc_pool {
+	struct device		*dev;
+	dma_addr_t		dma_addr;
+	void			*cpumem;	/* dma_alloc map */
+	size_t			desc_size;
+	size_t			mem_size;
+	size_t			num_desc;
+	struct gen_pool		*gen_pool;
+};
+
+void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
+{
+	if (!pool)
+		return;
+
+	WARN(gen_pool_size(pool->gen_pool) != gen_pool_avail(pool->gen_pool),
+	     "k3_knav_desc_pool size %zu != avail %zu",
+	     gen_pool_size(pool->gen_pool),
+	     gen_pool_avail(pool->gen_pool));
+	if (pool->cpumem)
+		dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
+				  pool->dma_addr);
+
+	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
+}
+
+struct k3_cppi_desc_pool *
+k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
+			      size_t desc_size,
+			      const char *name)
+{
+	struct k3_cppi_desc_pool *pool;
+	const char *pool_name = NULL;
+	int ret = -ENOMEM;
+
+	pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
+	if (!pool)
+		return ERR_PTR(ret);
+
+	pool->dev = dev;
+	pool->desc_size	= roundup_pow_of_two(desc_size);
+	pool->num_desc	= size;
+	pool->mem_size	= pool->num_desc * pool->desc_size;
+
+	pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
+				  GFP_KERNEL);
+	if (!pool_name)
+		return ERR_PTR(-ENOMEM);
+
+	pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
+	if (IS_ERR(pool->gen_pool)) {
+		ret = PTR_ERR(pool->gen_pool);
+		dev_err(pool->dev, "pool create failed %d\n", ret);
+		kfree_const(pool_name);
+		goto gen_pool_create_fail;
+	}
+
+	pool->gen_pool->name = pool_name;
+
+	pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
+					  &pool->dma_addr, GFP_KERNEL);
+
+	if (!pool->cpumem)
+		goto dma_alloc_fail;
+
+	ret = gen_pool_add_virt(pool->gen_pool, (unsigned long)pool->cpumem,
+				(phys_addr_t)pool->dma_addr, pool->mem_size,
+				-1);
+	if (ret < 0) {
+		dev_err(pool->dev, "pool add failed %d\n", ret);
+		goto gen_pool_add_virt_fail;
+	}
+
+	return pool;
+
+gen_pool_add_virt_fail:
+	dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
+			  pool->dma_addr);
+dma_alloc_fail:
+	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
+gen_pool_create_fail:
+	devm_kfree(pool->dev, pool);
+	return ERR_PTR(ret);
+}
+
+dma_addr_t k3_cppi_desc_pool_virt2dma(struct k3_cppi_desc_pool *pool,
+				      void *addr)
+{
+	return addr ? pool->dma_addr + (addr - pool->cpumem) : 0;
+}
+
+void *k3_cppi_desc_pool_dma2virt(struct k3_cppi_desc_pool *pool, dma_addr_t dma)
+{
+	return dma ? pool->cpumem + (dma - pool->dma_addr) : NULL;
+}
+
+void *k3_cppi_desc_pool_alloc(struct k3_cppi_desc_pool *pool)
+{
+	return (void *)gen_pool_alloc(pool->gen_pool, pool->desc_size);
+}
+
+void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr)
+{
+	gen_pool_free(pool->gen_pool, (unsigned long)addr, pool->desc_size);
+}
+
+size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool)
+{
+	return gen_pool_avail(pool->gen_pool) / pool->desc_size;
+}