Add a linked message at the top of cart page in Woocommerce

I'd like to add a link to my email subscription form at the top of my Cart page. I have the following cart related templates:

cart-empty.php
cart-item-data.php
cart-shipping.php
cart-totals.php
cart.php

If what I want is possible, do I add the necessary code in one of those, or in my functions.php?

Let me know if you want me to copy the code of any of those templates for the purposes of answering the question.

Solution

The following code will display a custom message with a linked text button in the top of cart page:

add_action('woocommerce_before_cart', 'add_cart_custom_notice');
function add_cart_custom_notice() {
    // HERE the link to your content
    $link = '#';

    // For example, print a notice with a linked button (the text is editable and translatable)
    wc_print_notice( sprintf( '<span class="subscription-reminder">' .
        __('Pellentesque habitant morbi tristique senectus et netus et malesuada fames  %s', 'woocommerce') . '</span>',
        '<a href='.$link.' class="button alt" style="float:right">'. __('Go to the subscription form', 'woocommerce') .'</a>'
    ), 'notice' );
}

Code goes in function.php file of your active child theme (or active theme). Tested and works.